HTML - Introduction

Let us first understand what HTML is and how does it contribute in the creation of a web page. HTML stands for Hyper Text Markup Language. It is a standard language for creating web pages. A web page is a document or file, written in HTML that is stored on a web server and can be viewed over the Internet using a web browser. A web browser is a program that automatically interprets the HTML codes and formats automatically. This process of interpreting the commands and displaying a web page appropriately is known as Rendering. A Web Server is a patient program that sits on your server (i.e. the physical machine dedicated to serving pages and performing other server functions) waiting to receive an HTTP request via TCP/IP. Any server configured to handle communications via TCP/IP has ports. These aren’t physical ports, like the serial port and parallel ports on the back of your computer, but they serve the same purpose. All HTTP requests come through port 80 unless the server has been configured differently. Port 80 is the default Web server port. Your server may be a file server, an applications server, and an FTP server. When an HTTP request comes through port 80 to the Web server, the Web server finds the page requested, checks the permissions of the client making the request, and, if the client has the appropriate permission, serves the page.


A website is an entire collection of web pages and other information (such as images, sound, and video files, etc.) that is made available through what appears to users as a single web server OR A collection of files that are arranged on the World Wide Web under a common address and allows retrieval via a browser.
HTML provides number of commands that can be used to place and format text, picture and sound on web pages. These formatting tags are known as Tags. Using HTML, a word or a phrase or even a picture can be linked to other documents or internet. 
HTML documents are typically written using text editor such as Windows Notepad and they are generally saved with .htm or .html extension. Elements are case-insensitive. Thus HTML documents are standard ASCII file with formatting commands that contains information about layout and link. 
After entering HTML code in a file, you can view it using any browser. The most popular browsers are Microsoft’s Internet Explorer, Netscape Navigator, Opera and there are many more. HTML is machine independent and all browsers accept the HTML code.
HTML Document Layout
The HTML document is usually divided into 2 structures. They are HEAD and BODY. Every tag is enclosed in a pair of angular brackets (<>). The opening tag begins with the left angular bracket followed by the tag name and then the right angular bracket. The closing tags are just like opening tags except that the tag name starts with a slash after the opening angular bracket.
Tags are of two types:
Empty Tags: Empty tags are those which did not need closing. For Example <BR> tag.
Non-Empty Tags: Non-empty tags are those which has to be closed. For Example </TITLE>