The Internet and website development. The Internet

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1 CHAPTER The Internet The Internet and website development Syllabus outcomes Describes and applies problem-solving processes when creating solutions Designs, produces and evaluates appropriate solutions to a range of challenging problems Critically analyses decision-making processes in a range of information and software solutions. Overview This chapter will develop your understanding of the Internet and intranets. It examines the uses of the Internet, Internet software and types of protocols used on the Internet. You will learn about the World Web Wide (www) and developing a website.

2 12. 1 The Internet and intranets The Internet (the Net ) is a connected set of networks using the TCP/IP standard. It links millions of computers all around the world. The Internet provides instant access to information such as news, weather reports, sports scores, share prices and educational material. It also provides services such as sending messages, banking, shopping, playing games and listening to music. People access the Internet in their homes, at school, at work or even at the beach. Establishing a connection to the Internet involves one of three basic types of connections: direct connection, dial-up connection and broadband connection. Direct connection is through a LAN and is used in many schools and organisations. Users are not required to dial-in, files are stored on their computer and response time is fast. Dial-up connections require a modem and telephone line. A typical connection is much slower and often less reliable than a direct connection. Modems are capable of delivering data at 56 Kbps or faster. Broadband connection uses a higher bandwidth than a dial-up connection and is much faster. The bandwidth is the capacity of the channel or transmission media. Broadband users are not required to dial-in and the Internet is available all the time. Both broadband and dial-up connection are delivered using normal telephone lines, a direct connection uses a dedicated data connection. Accessing the Internet requires an ISP. An Internet service provider (ISP) is an organisation that provides access to the Internet for a fee. There are hundreds of ISPs in Australia, such as Telstra BigPond, OptusNet and Oz (see Figure 12.1). Each ISP offers a different level of service and support for a specified charge. Figure 12.1 BigPond is an Internet service provider 262 HI Tech: Information and Software Technology

3 Historical perspective Even though the history of the Internet is relatively short it has undergone many significant developments. ARPANET (Advanced Research Projects Agency Network) was the basis of the Internet. It was established in 1969 by the US Department of Defence. The aim of ARPANET was to allow scientists at different locations to share information and protect against a nuclear attack. The ARPANET was built with no central authority because that would make the entire network vulnerable to attack. Telenet was the first commercial version of ARPANET and was launched in In 1979 Usenet was established with a focus on newsgroups. Newsgroups allowed users to conduct discussions on particular topics. In 1981 BITNET (Because It s Time Network) connected IBM mainframes around the educational community and the world to provide mail services. A link (gateway) was provided to connect BITNET to ARPANET. The Internet arrived in 1982 when ARPANET adopted the TCP/IP standard. The number of hosts on the Internet reached one thousand in The domain naming system (DNS) was first implemented in In 1986, the National Science Foundation (NSF) agreed to be the backbone for the US Internet service. It connected its huge network (NSFnet) to the Internet and provided five supercomputers to service the increasing volume of traffic. A friendly user-interface to the Internet started in A simple menu system called gopher was developed to access files and information for the University of Minnesota. HTTP (HyperText Transfer Protocol) was developed by Tim Berners-Lee for embedding links in text. In 1991 the World Wide Web (or Web) was introduced using this HTTP protocol. It has changed the appearance of the Internet. Mosaic was developed by Marc Andreessen in It was the first graphical browser to display hypertext documents. Lit 5.1 Interactive Intranet An intranet is a private network that uses a similar interface to the Web. It is essentially a smaller version of the Internet that exists within an organisation. Intranets support , newsgroups, file transfer, web publishing and are accessible to users by a browser. The main purpose of an intranet is to share information and computing resources among the members of an organisation. The information may be staff news, product information, telephone directories, policies, employee manuals and calendars. This information 12 The Internet and website development 263

4 can be displayed in a web page using a similar method to that used on the Internet. Extranet is an intranet that is accessible to customers, suppliers or others outside the organisation. It provides information such as product descriptions, frequently asked questions, warranties and how to contact customer service. Organisations are attempting to make extranets easy to use and a source of relevant information. Internet addresses Each computer connected to the Internet has a unique address called an IP address (Internet Protocol address). Most IP addresses use four bytes (32 bits) grouped in four 8-bit segments, separated by a full stop (period). For example, the IP Figure 12.2 An Internet address is used to locate information on the Web address for Microsoft is IP addresses are difficult for people to understand, so another addressing system is used based on a domain name. A domain name is the address of a specific computer on the Internet. Domain names are translated into IP addresses. Domain names are easier for people to remember than IP addresses as they are based on natural languages. A domain name consists of a number of separate parts. Each part is separated by a full stop and is called a domain. For example, the domain name : www stands for World Wide Web hi is the name of the specific computer com is the organisational domain au is the geographical domain. Organisational domains include edu for education, mil for military, gov for government, com for commercial, and org for non-profit organisations. The United States is the only country without a geographical domain, although some US sites have adopted us as the geographical domain. Geographical domains 264 HI Tech: Information and Software Technology

5 include au for Australia, uk for United Kingdom, fr for France, and ca for Canada. A URL (Uniform Resource Locator, pronounced you-are-el ) is the address of a file or resource on the Web. It is usually in lower case in a single unbroken line, with no spaces, such as: There are three parts to a URL: Protocol indicates access to a particular resource on the Web. For most cases the protocol will be It allows access to web pages based on hypertext. Domain name address of the specific computer where the resource is located such as The domain name is interchangeable with the IP address. File path full path to the file to be retrieved. It may be a simple file name or a directory path, such as /heinneman/default.htm. The domain name and the file path are separated by a forward slash (/). The file being retrieved in this example is default.htm. Exercise True or false? a Broadband connection uses a higher bandwidth than a dial-up connection. b The Internet arrived when ARPANET adopted DNS standard. c The Web was the first graphical browser. d A URL contains a domain name. 2 What am I? a An organisation that provides access to the Internet for a fee. b The basis of the Internet. c Private network that uses a similar interface to the Web. d The address of a specific computer on the Internet. 3 Copy and complete the following by replacing the letter in brackets with a suitable term: The Internet is a connected set of (a) using the TCP/IP standard. A dial-up connection requires a (b) and telephone line. The (c) was introduced in 1991 using the (d) protocol. 4 a What is provided by the Internet? b List three ways of establishing a connection to the Internet. c What contribution did the NSF make to the development of the Internet? d Explain the difference between an intranet and an extranet. e Describe an IP address. f What is a URL? 12 The Internet and website development 265

6 Development 5 Do research into the history of the Internet. Identify the key historical events for the Internet. Include additional events not mentioned in this section. Construct a timeline of these events. Briefly describe and state the importance of each event. 6 Compare and contrast an intranet and the Internet. Outline the features of the school intranet Uses of the Internet The Internet has many different uses such as , research, chatting and messaging. (electronic mail) is the transmission of electronic messages using a computer. is the most widely used Internet service. It requires software to send, receive and manage . Most browsers include an component and there are also separate applications such as Microsoft Outlook Express and Netscape Mail. In addition to software the user needs an account and an address. addresses are unique and consist of two parts separated by ( at ) symbol in the form name@domain name. The first part is the name of the account. It is often a person s username and is chosen where a user signs up for an account. The second part is the domain name. It is the location of the person s account on the Internet. The domain name identifies the specific computer or server where the messages are stored. For example, the address adam@yahoo.com consists of the following parts: adam is the username yahoo is the name of the account on the Internet com is the organisational domain. An message is usually short without a lot of details. When is sent, it is stored on the server where the recipient has an account. It stays on the server until the person checks their . is sent using a header. The header contains information needed to deliver the message. The sender s address is usually automatically inserted. The header contains four main parts: To address is the address of the person receiving the message, which must be correctly typed 266 HI Tech: Information and Software Technology

7 Cc carbon copy sends the same message to other people apart from the main recipient Bcc blind carbon copy sends a copy to other people without revealing who else got the message Subject is the topic of the message or brief description this is very useful for the receiver of Figure message the message. After the is read it can be deleted, printed or stored in an appropriate folder. The user can reply to an message simply by clicking on the Reply or Respond To command. A new message window is opened with the address of the original sender automatically inserted. The previous message can be retained to remind the person of their original message. This is called quoting. The prefix Re: may be added to the original subject line to identify the thread of the message. Forwarding messages involves sending messages you receive to someone else. An address book is used to store addresses. This saves time typing the address and avoids the problem of remembering each address. A mailing list is a group of people who want to receive the same messages. A signature is several lines automatically added to the end of all messages. It may include an address, website, graphic, occupation and telephone number. An attachment is a file in its original condition and format that is sent with the message. It can be any kind of file, including text, graphic, video, audio or a program. Attachments are a useful means of file transfer, as the receiver of the attachment will have an exact copy of the file. To send an attachment click the Attach or Insert File command and select the file you want to send. When sending an attachment it is important to include a brief explanation in the main body of the message. The file name and the format of the attachment should be easily understood. Netiquette is a code of acceptable behaviour users should follow on the Internet. It covers rules for all aspects of the Internet such as the , chatting, newsgroups and discussion groups. If you follow the rules of netiquette, you will be doing your part to make 12 The Internet and website development 267

8 life on the Internet easier for everybody. Some of the rules for netiquette include: keep messages short and to the point be polite and avoid offensive language avoid sending abusive or insulting messages (flames) do not participate in flame wars avoid using all capital letters as it is considered shouting use emoticons to express feelings such as :) for happy or :( for sad use abbreviations and acronyms such as IRL for in real life or BTW for by the way make the subject line as meaningful as possible. Research A search engine is a program that finds websites and web pages. It accesses a database of indexed websites that can be searched using a keyword. This index is built by regularly scanning for new websites and accepting submissions from website authors. A search engine is accessed using a browser. There are dozens of search engines available on the Web, including Yahoo!, Alta Vista and Google (see Figure 12.4). Each search engine has a different method of building its index and often obtains different results from the same search. Some search engines provide web directories. A web directory organises the Web into categories and then smaller subcategories. This allows the user to browse through the categories until they find a relevant site. Search engines require the user to enter one or more keywords related to their topic of interest. Most search engines allow users to search for specific items such as images. When the user enters a keyword and clicks the Search button, the search engine scans its index and lists the websites that contain that keyword. Some search engines allow a search to be restricted to just Australia. This can be an advantage when researching. The Figure 12.4 Yahoo! is one of many search engines on the Internet listing of websites 268 HI Tech: Information and Software Technology

9 is usually in order of relevance and is in the form of hyperlinks. This allows the user to access the listed web pages by simply clicking them. Selecting a keyword is crucial to the success of a search. To avoid being overloaded with information it is sensible to use keywords that are very specific. Advance search options provide users with more accurate results. The search can be restricted to files that were updated recently, particular file formats or websites without certain words. Chatting A chat provides a real time conversation with one person or with hundreds of people. People meet for a chat in a chat room (or chat channel). A chat room is a virtual room usually on a particular topic where people talk in groups or privately. To start a chat the user connects to a chat server through a chat program. A chat program is included in your browser or can be downloaded from the Internet. Chat rooms supporting voice chats and video chats, where you can hear and see others, are becoming more popular. Most chat rooms are open for everybody and users can contribute to ongoing discussions by typing a few lines. People make friends and even have met future partners through chat sessions. However, people can make up different personalities and pretend to be anything they want to be. There are dangers for users, particularly children, from being exploited. Personal information such as address, phone number or bank details should never be given out in a chat session. Archie was developed in 1989 at McGill University in Canada. It was the first search engine. Administrators found out that half the traffic going into Canada was accessing Archie on their computer. They closed down Archie to outside access. Messaging A newsgroup is an online area in which users conduct discussions on a particular topic. People read messages and join in discussions by sending or posting messages. The entire collection of newsgroups is called the Usenet (Users network). Newsgroups are read each day by people from all over the world and provide a large diversity of opinion and knowledge. Each newsgroup is classified into eight major categories: computers (comp.), social issues (soc.), science (sci.), recreation (rec.), discussion (talk.), miscellaneous (misc.), newsgroups (news.) and alternative (alt.). A message board (or discussion group) is a popular web-based discussion group (see Figure 12.5). Message boards are provided by many websites. Discussion groups contain useful information. For example, FAQ (frequently asked questions) provide concise and 12 The Internet and website development 269

10 Figure 12.5 Discussion group detailed information relevant to that group. Some discussion groups and newsgroups are only for authorised members and require a username and password. For example, a discussion group for a university course would be restricted to students taking that course. Instant messaging (IM) is a real-time Internet service that notifies users when one or more people are online. It has become one of the most popular Internet activities. Instant messaging services are provided by many organisations such as ICQ, AOL, Microsoft and Yahoo!. They enable users to create buddy lists, check whether a buddy is online and exchange messages. There are currently no standards for instant messaging. Individuals on a buddy list need to be on the same or compatible instant messaging program. Exercise Explain the difference between: a and chatting b an attachment and a search engine c forwarding and replying. 2 Copy and complete the following sentences: a are unique and consist of two parts separated by symbol. b A mailing is a group of people who want to receive the same messages. c A web directory organises the Web into. d A is a popular web-based discussion group. 3 What am I? a Used to store addresses. b Code of acceptable behaviour users should follow on the Internet. c Online area in which users conduct discussions on a particular topic. d Real-time Internet service that notifies users when one or more people are online. 270 HI Tech: Information and Software Technology

11 4 a List the four parts of an header. b Explain how a user replies to an message. c Describe some of the rules for netiquette. d How does a search engine work? e What is a chat room? f What is provided by an instant messaging service? Development 5 Create or obtain two addresses. a Create a brief message. b Send an message to one of the addresses. c Send a carbon copy and blind carbon copy to a friend. d Read and reply to the message. e Create a simple mailing list. f Create and send an message that contains an attachment. 6 Use three different search engines to find information about netiquette. Compare and contrast the results of the three search engines. Which search engine do you prefer? Give reasons for your answer Internet software and protocols There is a range of Internet software and types of protocols over the Internet. Browser software A web browser (or browser) is a software program that allows users to access and view web pages. The most widely used web browsers are Internet Explorer and Netscape Navigator (see Figure 12.6). Online service providers (OSP) such as America Online (AOL) and CompuServe provide a browser free of charge as part of their subscription package. Web browsers display web pages, link to other web pages and download information to your computer. Figure 12.6 Internet Explorer is one web browser 12 The Internet and website development 271

12 A web browser will display a website if the address (or location) is entered directly into the browser. Web pages that have video and animation take longer to download, as they are larger in size. Browsers have the ability to store the addresses of frequently used websites. These stored addresses are called favorites or bookmarks. Favorites save time accessing frequently used web pages. The websites recently visited are called history. History can be displayed using the browser. Web browsers also have a range of commands or buttons that make them easier to use. Table 12.1 Browser commands Command or button Back Forward Stop Refresh Home Search Favorites/Bookmark Use Displays the previous web page Displays the next web page Interrupts the download of a web page Reloads the current web page from the server Returns to the home page Displays web search tools Addresses of frequently used websites Tutorial Web authoring software Web authoring software is used to create and manage a multimedia website. Websites contain a range of data types such as animation, audio and streamed video. The web authoring software will position and display objects, as they would be viewed through a web browser. Many programs allow the user to manage entire websites using tools that automate repetitive tasks. Some popular web authoring software includes: Macromedia Dreamweaver currently the industry standard used by professional designers. It creates HTML code that is lean and compatible with any browser or platform. Microsoft FrontPage used by small business and home users. It has an intuitive layout with easy to use templates. Users have the ability to view and edit the HTML code (see Figure 12.7). Web authoring software allows the user to create a website structure. This may involve different levels and arranging groups of pages. Authoring software is designed to handle different data types. Text is created and formatted in many different ways such as using different fonts. Text can be placed in ordered and unordered lists. Images are added to a web page and edited as required. Users can also create 272 HI Tech: Information and Software Technology

13 and edit thumbnails. Audio, animations and video are easily inserted onto a web page. Authoring software also allows users to create tables, frames and forms. These are powerful tools used to create professional web pages. Types of protocols A protocol is a set of rules that governs the transmission of data between computer devices. Some of the protocols used on the Internet include TCP/IP, HTTP, FTP and SMTP. Transmission Control Protocol/Internet Protocol (TCP/IP) is a common language for data transmission and error detection across the Internet. It works by breaking information into smaller packets of data. Each data packet contains the information and the address of the receiving computer. The TCP standards inform the receiving computer what is inside the data packet and the IP standard tells the computer where and how to send the packet. Each data packet might take a different route but eventually reaches the same destination where all the packets are reassembled into the original information. Hypertext transfer protocol (HTTP) is a standard for transferring the contents of a web page into a browser for viewing. It does not download files that make up the web page. HTTP is a one-way system as data is only transferred from the web server to the browser. Whenever http appears in a URL the user is connecting to a web server and using the HTTP standard. File transfer protocol (FTP) is a standard to upload and download files. An FTP server is a computer that allows users to upload and download files using FTP. Whenever ftp appears in a URL the user is connecting to a file server and not a web server. Some form of file transfer will then take place. Simple mail transfer protocol (SMTP) is a standard for outgoing . Most messages are sent using SMTP. POP3 (Post Office Protocol) is a standard for incoming . TCP/IP was originally developed by the United States Department of Defence for computers using the UNIX operating system. It is now used by every computer on the Internet. Figure 12.7 Popular web authoring software for the home user includes Microsoft FrontPage 12 The Internet and website development 273

14 Project: My website Preneeth Kumar is a student who wants to create a website about his family, friends and interests. His sister Rani has agreed to supervise and assist in the development of the website. Preneeth solved the problem using the four stages in project development. Define and analyse the problem: Preneeth surfed the Internet and gathered design ideas from other personal websites. He investigated the possibility of including pictures and videos of the family. A project plan was written. Design possible solutions: Preneeth developed two possible solutions. Each solution had a different website structure and design. Both solutions had a large multimedia component. Preneeth made a choice and presented his recommendation to his sister. Rani agreed but suggested a simplified version. Produce the solution: The website was constructed using Microsoft FrontPage. He created the website structure and used a consistent layout for each page. Preneeth imported pictures, audio and video into the appropriate pages. Links were added and tested. His sister provided some technical advice on using tables and creating animation. Web pages and files were uploaded to a web server to become part of the Internet. Evaluate the solution: Preneeth tested his website using another computer. He checked each web page and ensured all links were working. Preneeth was happy with his website. Tasks ICT Outline a website structure that would be appropriate for this project. 2 Describe any social and ethical issues that would be a concern in this project. Exercise Copy and complete the following sentences: a Web software is used to create and manage a multimedia website. b The refresh command the current web page from the server. c The interrupts the download of a web page. d is a standard for incoming mail. 2 True or false? a OSPs provide a browser as part of their subscription package. 274 HI Tech: Information and Software Technology

15 b c d The back command displays the next web page. TCP/IP is a common language of data transmission and error detection over the Internet. FTP is a standard for outgoing . 3 Copy and complete the following by replacing the letter in brackets with a suitable term: A web (a) is a software program that allows users to access and view web (b). It will display a website if the (c) is entered directly into the browser. Web pages that have video take longer to (d). 4 a What is the advantage of Favorites or Bookmarks? b Describe a website structure. c What is a protocol? d How does the TCP/IP work? e What protocol is used to upload and download files? f What is the hypertext transfer protocol? Development 5 Examine the range of software in your school to create a website. Investigate any templates and wizards available with this software. Which piece of software do you prefer? Give reasons for your answer. 6 Create a web page that briefly describes the types of protocols used on the Internet. Do research into Internet protocols to ensure that the information on your web page is current World Wide Web The World Wide Web (www, also the Web) consists of a worldwide collection of electronic documents that use the HTTP standard. The Web provides a user-friendly interface to the Internet. Resources on the Web are organised so that users can easily move from one resource to another. The connections to other computers are made automatically without being seen by the user. These connections are made with the use of hypertext and a browser. A browser allows users to access and view websites. A website is a group of electronic documents that present information on a particular topic. Each electronic document is called a web page. A web page can contain text, images, sounds, video clips and links to other pages. Web pages are stored on powerful computers called servers or web servers. Each server may store thousands of web pages from different websites. To view a particular web page your computer asks the server for a particular page to be sent. Lit The Internet and website development 275

16 Figure 12.8 The ninemsn website contains different types of information The Web is an information medium that covers a vast range of topics on all aspects of society. It is used to access research, businesses, entertainment, software and personal interests. A key feature of the Web is interactivity. It allows the user to choose their experience on the Web. For example, you can access information, communicate using , download software, listen to music, watch a video or play an interactive game. There are many types of websites: commercial exist to sell their goods or services information present factual data business sites that provide support for an organisation such as technical support news present information on the current events, sports, money, life and weather (see Figure 12.8) portal provide Internet services such as search engines, , news, sports and reference material personal an individual s web page and these sites contain information on every topic. Internet security The Internet has generated a whole underground industry of threats such as viruses, hackers and spam. However, there are many ways of controlling access to information on the Web. A cookie is a file that is stored on the hard disk after the user visits a website. It is used to measure a user s behaviour and work flow habits. Privacy is often an issue raised with cookies. Cookies store the information about the web pages visited and the transactions 276 HI Tech: Information and Software Technology

17 completed. However, most cookies are designed to improve your experience and allow organisations to target advertisements to your tastes. Users do have the option of blocking all cookies or having your browser prompt you before accepting cookies. A proxy server is a barrier to the Internet to ensure users are securely and productively accessing network resources. It lets administrators limit access to objectionable content by filtering URLs. Administrators can control user access to specific documents or websites. Proxy servers distribute and manage information reducing network traffic and user wait times. Traffic time is reduced as the proxy server caches frequently accessed documents or entire websites. The proxy server only requests data from its source when that source has been updated or has expired. Firewalls are used on the Internet or any network to check all incoming data for the purpose of verification and authentication. It aims to protect a computer system from hackers trying to access sensitive information. Firewalls are an important security measure on an intranet. All messages entering or leaving the intranet pass through the firewall. It examines each message and blocks those that do not meet the specified security criteria. On large systems more than one firewall is necessary because barriers need to be placed at all critical points. Anti-virus software is used to scan a file or disk for a range of known viruses. A virus is a small program that attaches itself to an application. There is no guarantee that anti-virus software will stop every virus, as new viruses are constantly appearing. However, if users download the latest virus definition files and regularly use the anti-virus program it will minimise the problem. Anti-virus software will also protect against viruses, worms and Trojan horses. An virus attaches itself to an message. It spreads by Proxy server automatically mailing itself to each contact in the user s address book. Internet Worms have the ability to Firewall copy themselves from machine to machine. Worms normally move around and infect other machines through networks. Trojan horses Figure 12.9 Proxy server Lit 5.3 User User User 12 The Internet and website development 277

18 The term spam comes from a Monty Python sketch called the The Black Eagle. The sketch contained an annoying and repetitive song about spam. are programs that claim to be one thing, such as a computer game, but will cause damage when the program is started. Spam blocking software is protection against spam. Spam is the sending of a message through the Internet as a mass mailing to a large number of recipients. The message is unwanted and often commercial. Fighting spam has been an ongoing battle. Antispammers develop a tool to block spam and spammers defeat the tool. For this reason spam blockers need to be regularly updated. There are different technologies used to block spam. The success of spam blocking software is not only the quantity of spam it stops but also ensuring genuine is received. Anti-spyware software is protection against spyware. Spyware is software that installs on a computer in secret and transmits data from that computer. The data transmitted is usually personal information or information about computer usage. Users are infected with spyware when they visit a website and are tricked into installing it or they download a program with a spyware component. The spyware component may be advertising software or adware. Anti-spyware software is a tool that removes spyware and prevents it from being installed. Exercise What am I? a A worldwide collection of documents that use the HTTP standard. b A file that is stored on the hard disk after visits to a website. c Checks all incoming data for the purpose of verification and authentication. d A program that claims to be one thing but will cause damage when the program is started. 2 Copy and complete the following by replacing the letter in brackets with a suitable term: A (a) is a group of electronic documents that present (b) on a particular topic. Each electronic document is called a web (c). Websites are stored on powerful computers called (d). 3 Unjumble these words: a ewb gepa b oxpry rseevr c asntirviu aroswfte 4 a What is a key feature of the Web? b List six different types of websites. c What is the purpose of most cookies? d How does a proxy server improve security? 278 HI Tech: Information and Software Technology

19 e f How is a firewall used on an intranet? What is spam? Development 5 Find at least one website where the focus is commercial, information, business, news, portal and personal. What are the features of these websites? Justify your classification of these websites. 6 Why is the Web an important medium to publish information? Describe the ways the Web is different from other publishing media Website development A website is made up of three types of web pages: home page, intermediate pages and content pages. Home page (index page) is the first page viewed by a visitor. It provides information about the purpose and subject matter of the website. A home page provides a link to other web pages. Many websites have intermediate pages. An intermediate page is the next level down from the home page. An intermediate page is accessible from the home page and links back to the home page. Intermediate pages provide structure and assist in the navigation of the website. They are a way of grouping the content pages. Content pages contain topic details and are usually accessible from intermediate pages. Content pages usually contain a link back to the home page. Hypertext markup language (HTML) is used to create web pages. HTML is a set of special instructions (called tags) that indicate how parts of a document will be displayed. HTML code can be created with any word processor or text editor, however, you Lit The Internet and website development 279

20 Tim Berners-Lee developed a method of Internet addressing called URL, the language for encoding and displaying hypertext documents called HTML and a method of linking hypertext documents called HTTP. do not need to write HTML code to create a web page. Many programs will automatically convert basic formatting features into HTML codes. Web authoring software is used to create and manage a website. You can layout text and graphics exactly the way you want them to look and the software creates the HTML code. Features of a website The features of websites are changing to take advantage of new developments in information technology. Some common features found in websites include: Contact information traditional contact information is needed on most websites such as address, phone, fax and . It is appropriate to include as many different contact methods as possible. Text the look and style of text is an important factor in a web page. The text content of a web page should display the essential content. Graphic pictures add interest and attraction to a web page. The most common formats for web images are JPEG and GIF. Thumbnail image small preview representation of the real full size image. It downloads faster than the full size image. If a visitor wants to see the full size image they simply click on the thumbnail. Rollover picture, icon or button that changes when the mouse is moved over it. A rollover is actually two images: one image for the on condition and one image for the off condition. GIF file format is often used for images as they must be displayed quickly. Animation a flashing object quickly gets the visitor s attention. It is used to direct the visitor to an area of the screen or an interesting feature. Streamed audio used to provide background music or sound effects. Streaming audio is heard before the entire file has been transferred. Streamed video video clips that play before the entire file has been transferred. It is more dependent than streamed audio on a high bandwidth. Hyperlink a link to another part of the same web page, a separate web page, or location on the Internet. Hyperlinks are made using text (hot word) or image (hot spot). Links are usually identified using an underlined character and/or a different text colour. Popular graphic links use buttons and 280 HI Tech: Information and Software Technology

21 icons. Links are often arranged in horizontal rows or vertical columns to form a navigation toolbar. Tables rows and columns of cells that are filled with characters or graphics. Tables are used to arrange information in a precise row and column format. A variety of attributes can be applied to tables and their cells, such as shading and borders. Lists unordered lists do not have a numbered sequence. Entry in an unordered list is usually shown with a bullet. Ordered lists provide a more structured look using a numbered sequence. Frames space or boxes that hold an object. Each frame is considered a separate window and could be a separate HTML document. Frames allow a banner, advertising message or animation to be held in place while the visitor navigates the website. Web forms are tools to collect information, such as orders for goods and services and results from surveys. Web forms have an invisible part that processes the data and stores it in a database. Information is entered using text boxes, option buttons, check boxes, list boxes, spin boxes. Figure Features of a website (these materials have been reproduced with the permission of ebay Inc. Copyright ebay Inc. All rights reserved) Designing a website There are three basic design principles for a website (see Figure 12.11): Consistency layout, format and style should be the same throughout the website unless different data types demand a change. Readability is improved when similar items are grouped. Navigation people need to understand the structure of the web pages. Colouring different areas of the page, using visual symbols (icons and arrows), inserting clear page headers and creating simple hyperlinks improves navigation. Simplicity do not overuse design elements as this will create visual clutter and confuse the visitor. The overuse of colour, 12 The Internet and website development 281

22 Figure Website Tips Lit 5.5 sound and animations can be distracting. First impressions on the Web are important. A visitor often forms an opinion of a website within the first minute of accessing the home page. In addition to the above design principles there are design factors for these elements: Text clear and legible text using at most three different fonts. Care should be taken using font styles such as bold and italic. Underlining is only used for hyperlinks. Long lines of text are difficult to read. Colour many different colours can be distracting and reduce readability. A colour scheme should not interfere with the main message of the web page. Dark text on a light background or vice versa usually works well. Blue is often preferred for unused links and purple for used links. Graphics are used to create interest, however, they are slow to download. When using graphics consider the size of the graphic, recognisable icons and whether the graphic fits easily on the screen. Animation visitors seeking information from a website are distracted by inappropriate animation. A small creative animation such as a comet-type effect can be effective. Audio and video should not be an essential part of a web page as some visitors might not have the right hardware or plug-in. It is good practice to advise visitors about the size of audio and video files. 282 HI Tech: Information and Software Technology

23 Exercise Copy and complete the following sentences: a A image is a small preview representation of the real full size image. b Links are usually identified using an character and/or a different text colour. c Each is considered as a separate window and could be a separate HTML document. d Many different colours can be distracting and reduce. 2 True or false? a HTTP is used to create web pages. b Streaming audio is heard before the entire file has been transferred. c Ordered lists are usually shown with a bullet. d Web forms have an invisible part that stores data in a database. 3 What am I? a The first page viewed by a visitor to a website. b A set of special instructions that indicate how parts of a document will be displayed. c A picture, icon or button that changes when the mouse is moved over it. d Rows and columns of cells that are filled with characters or graphics. 4 a Describe an intermediate page of a website. b How do you create HTML code? c Identify the contact information that is needed on most websites. d What is a hyperlink? e Describe some of the information often displayed in a frame. f Why is navigation an important design element? Development 5 Investigate the features of three different websites. Identify the features that you like and those you dislike. Write a report that summarises your investigation. 6 Create a simple website on a topic you find interesting. a Describe the features of the website. b Create and test the navigation used in your website. ICT The Internet and website development 283

24 Part A: Multiple choice questions Select the alternative (a), (b), (c) or (d) that best answers each question. 1 Which of the following describes a historical event introduced in 1991 using the HTTP standard? a ARPANET b World Wide Web c d NSFnet 2 Which of the following is a private network that uses a similar interface to the Web? a Intranet b Extranet c ARPANET d BITNET 3 Which of the following is a program that finds websites and web pages? a Find command b Search program c Search engine d Attachment 4 Which of the following describes chatting? a b c d Online area in which users conduct discussions on a particular topic A popular web-based discussion group A real-time Internet service that notifies users when more than one person is online A real-time conversation with one person or with hundreds of people 5 Which of the following is a standard to upload and download files? a SMTP b FTP c HTTP d TCP/IP 6 Which of the following is a command or button that stores the addresses of frequently used websites? a Explorer b Save c Favorite d List 7 What is a proxy server? a A barrier to the Internet to ensure users are securely and productively accessing network resources b A file that is stored on the hard disk after the user visits a website c A computer used to store web pages d A computer used to store 8 Which of the following statements is incorrect? a Cookies are an important security measure for the intranet b Fighting spam has been an ongoing battle c Anti-virus software is used to scan a file or disk for a range of wellknown viruses d Worms have the ability to copy themselves from machine to machine 9 Which of the following is a set of special instructions used to create web pages? a HTTP b Hypertext c HTML d Web manager 10 Which of the following describes a picture, icon or button that changes when the mouse is moved over it? a Thumbnail b Rollover c Hyperlink d Graphic 284 HI Tech: Information and Software Technology

25 Part B: Match the term For each of the following statements (1 to 10), select from the list of terms (a to j) the one that most closely fits the statement. Statements 1 A connected set of networks using the TCP/IP standard. 2 A private network that uses a similar interface to the Web. 3 An online area in which users conduct discussions on a particular topic. 4 Transmission of electronic messages using a computer. 5 A program that finds websites and web pages. Terms a Cookie b c Home d HTTP e Internet 6 A software program that allows users to access and view web pages. 7 A standard for transferring the contents of a web page into a browser for viewing. 8 A worldwide collection of electronic documents that use the HTTP standard. 9 A file that is stored on the hard disk after the user visits a website. 10 The first page of a website. f g h i j Intranet Newsgroup Search engine Web Web browser Part C: Extended response questions Write at least one paragraph for each of the following: 1 Describe four major events in the history of the Internet. Which event do you consider the most important? Give a reason for your answer. 2 The Internet is having a significant impact on our society. Outline four ways we are using the Internet. 3 Explain the difference between these terms: a HTTP and FTP b web browser and web authoring software. 4 What is the World Wide Web? Your answer should explain interactivity, websites and web pages. 5 Spam is causing a problem for many people. Why is spam a problem? How can spam be reduced? 6 Tables, lists and frames are an important feature of many websites. Distinguish between these tools. e Tester 12 The Internet and website development 285

26 Project: Internet website Create a website that presents information about the Internet. Suggested topics could include history of the Internet, intranets, , search engines, chatting, messaging, browsers, authoring software and some aspect of Internet security. This is a group project that requires each member to create at least one page in the website. The design of the website and the navigation are important characteristics for this project. Your solution should be developed using the four stages in project development. Project 5.1 Project 5.2 Project 5.3 Cross project 2 Cross project 3 Cross project HI Tech: Information and Software Technology