Short notes on webpage programming languages

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1 Short notes on webpage programming languages What is HTML? HTML is a language for describing web pages. HTML stands for Hyper Text Markup Language HTML is a markup language A markup language is a set of markup tags The tags describe document content HTML documents contain HTML tags and plain text HTML documents are also called web pages HTML Tags HTML markup tags are usually called HTML tags HTML tags are keywords (tag names) surrounded by angle brackets like <html> HTML tags normally come in pairs like <b> and </b> The first tag in a pair is the start tag, the second tag is the end tag The end tag is written like the start tag, with a forward slash before the tag name Start and end tags are also called opening tags and closing tags Syntax for a basic html page: <!DOCTYPE html> <html> <body> <h1>my name is..</h1> <p>my first paragraph</p> </body> </html> Example Explained The DOCTYPE declaration defines the document type The text between <html> and </html> describes the web page The text between <body> and </body> is the visible page content The text between <h1> and </h1> is displayed as a heading The text between <p> and </p> is displayed as a paragraph HTML Hyperlinks (Links) The HTML <a> tag defines a hyperlink. A hyperlink (or link) is a word, group of words, or image that you can click on to jump to another document. When you move the cursor over a link in a Web page, the arrow will turn into a little hand. 1

documents are also called web pages HTML Tags HTML markup tags are usually called HTML tags HTML tags are keywords (tag names) surrounded by angle brackets like <html> HTML tags normally come in

2 The most important attribute of the <a> element is the href attribute, which indicates the link's destination. By default, links will appear as follows in all browsers: An unvisited link is underlined and blue A visited link is underlined and purple An active link is underlined and red HTML Link Syntax The HTML code for a link is simple. It looks like this: <a href="url">link text</a> The href attribute specifies the destination of a link. Example: <a href=" W3Schools</a> HTML Images - The <img> Tag and the Src Attribute In HTML, images are defined with the <img> tag. The <img> tag is empty, which means that it contains attributes only, and has no closing tag. To display an image on a page, you need to use the src attribute. Src stands for "source". The value of the src attribute is the URL of the image you want to display. Syntax for defining an image: <img src="url" alt="some_text"> Example: <img src="smiley.gif" alt="smiley face What is CSS? CSS stands for Cascading Style Sheets Styles define how to display HTML elements Styles were added to HTML 4.0 to solve a problem External Style Sheets can save a lot of work External Style Sheets are stored in CSS files JavaScript is a Scripting Language A scripting language is a lightweight programming language. JavaScript is programming code that can be inserted into HTML pages. JavaScript code can be executed by all modern web browsers. JavaScript is easy to learn. 2

HTML code for a link is simple. It looks like this: <a href="url">link text</a> The href attribute specifies the destination of a link. Example: <a href="http://www.w3schools.

3 What is XML XML stands for extensible Markup Language. XML is designed to transport and store data. XML is important to know, and very easy to learn Classic ASP - Active Server Pages Active Server Pages (ASP), also known as Classic ASP, was introduced in 1998 as Microsoft's first server side scripting engine. ASP is a technology that enables scripts in web pages to be executed by an Internet server. ASP pages have the file extension.asp, and are normally written in VBScript. If you want to learn Classic ASP ASP.NET ASP.NET is a new ASP generation. It is not compatible with Classic ASP, but ASP.NET may include Classic ASP. ASP.NET pages are compiled, which makes them faster than Classic ASP. ASP.NET has better language support, a large set of user controls, XML- based components, and integrated user authentication. ASP.NET pages have the extension.aspx, and are normally written in VB (Visual Basic) or C# (C sharp). User controls in ASP.NET can be written in different languages, including C++ and Java. When a browser requests an ASP.NET file, the ASP.NET engine reads the file, compiles and executes the scripts in the file, and returns the result to the browser as plain HTML. What is PHP? PHP is an acronym for "PHP Hypertext Preprocessor" PHP is a widely- used, open source scripting language PHP scripts are executed on the server PHP costs nothing, it is free to download and use What is a PHP File? PHP files can contain text, HTML, CSS, JavaScript, and PHP code PHP code are executed on the server, and the result is returned to the browser as plain HTML PHP files have extension ".php" 3

scripting engine. ASP is a technology that enables scripts in web pages to be executed by an Internet server. ASP pages have the file extension.asp, and are normally written in VBScript.

4 What Can PHP Do? PHP can generate dynamic page content PHP can create, open, read, write, and close files on the server PHP can collect form data PHP can send and receive cookies PHP can add, delete, modify data in your database PHP can restrict users to access some pages on your website PHP can encrypt data With PHP you are not limited to output HTML. You can output images, PDF files, and even Flash movies. You can also output any text, such as XHTML and XML. Why PHP? PHP runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.) PHP is compatible with almost all servers used today (Apache, IIS, etc.) PHP supports a wide range of databases PHP is free. Download it from the official PHP resource: PHP is easy to learn and runs efficiently on the server side What is SQL? SQL stands for Structured Query Language SQL lets you access and manipulate databases SQL is an ANSI (American National Standards Institute) standard What Can SQL do? SQL can execute queries against a database SQL can retrieve data from a database SQL can insert records in a database SQL can update records in a database SQL can delete records from a database SQL can create new databases SQL can create new tables in a database SQL can create stored procedures in a database SQL can create views in a database SQL can set permissions on tables, procedures, and views SQL is a Standard - BUT... Although SQL is an ANSI (American National Standards Institute) standard, there are different versions of the SQL language. 4

your database PHP can restrict users to access some pages on your website PHP can encrypt data With PHP you are not limited to output HTML. You can output images, PDF files, and even Flash movies.

5 However, to be compliant with the ANSI standard, they all support at least the major commands (such as SELECT, UPDATE, DELETE, INSERT, WHERE) in a similar manner. Note: Most of the SQL database programs also have their own proprietary extensions in addition to the SQL standard! Using SQL in Your Web Site To build a web site that shows data from a database, you will need: An RDBMS database program (i.e. MS Access, SQL Server, MySQL) To use a server- side scripting language, like PHP or ASP To use SQL to get the data you want To use HTML / CSS RDBMS RDBMS stands for Relational Database Management System. RDBMS is the basis for SQL, and for all modern database systems such as MS SQL Server, IBM DB2, Oracle, MySQL, and Microsoft Access. The data in RDBMS is stored in database objects called tables. A table is a collection of related data entries and it consists of columns and rows. 5

HTML Basics(w3schools.com, 2013)

HTML Basics(w3schools.com, 2013) What is HTML? HTML is a language for describing web pages. HTML stands for Hyper Text Markup Language. HTML is a markup language A markup language is a set of markup tags.