CSS

What is CSS?

CSS stands for Cascading Style Sheets. One can display his web page as he like what he want to see by css. It is a text file (.css). composed of lines of code that tell browsers how to display     an HTML page. Styles define display system of HTML elements. Styles were added to HTML 4.0 to solve a problem. Style can be done internally of externally. External Style Sheets can save a lot of work. Style sheets are a very powerful tool for the Web site developer.  

How does CSS works

    When any visitor browse some sites. Firstly one of page load to his computer form server. Content of loaded page is HTML code along with CSS code or style sheet linked to sime txt or video or any other file. This code or sheet may be embedded or externally added a CSS file. Brower will interpret this code by using it particular rendering engine of apply the CSS to the HTML file and display the page to browser.

The code of downloaded page is interpreted then rendering, same way the css code will interpreted then rendering and finally display to the browser.

The W3C has developed standard of CSS and HTML and  has gone to great lengths to specify how browser manufacturers should render the code, but bugs, omissions, and misinterpretations still creep in, meaning that no two browsers will render a Web page exactly the same. For the most part, these differences will go unnoticed by the user, but occasionally these differences are glaring and require you to do some extra work to get the page to look right in the broadest spectrum of browsers.

Why use it?

    The main reason of using CSS is to separate HTML contant from its apperance. It is possible to use in-line embedded css code to HTML file or create an another file(.CSS). If any one create a CSS file, this saves time and allows for easier site maintenance.
For example, if one wanted to change the font style or anything else of all the links in a website from "Arial" to "Tahoma", There are two way to do this. He can go every HTML page (if in-line code in HTML) and change every link. It is very time consume and difficult. Otherway if he used a separate CSS file, he allow to just go to CSS file and change to specific link and save. Then whole pages link will change to ‘Tahoma’ from ‘Arial’. It takes vary small amount of time but performance is very high.
Since there would not be as much to change, the possibility of introducing errors into the website also goes down, saving even more time. As a separate file, a style sheet can be readily modified for different types of browsers and devices, further extending web accessibility to all types of users.      

Advantages of CSS :   

• More Precise Formatting
• Separation of HTML Content from Appearance
• Saves Time
• Easier Site Maintenance
• Web Accessibility
• Very Reliable
• High Accuracy
• Can rapidly change easily
• CSS Saves a Lot of Work!

Why not to use it?

No system is 100% ok. So CSS has some limiatations. W3C making standard for CSS. It is a continuous process. So earliear versions of various brawoser does not suport later version of CSS.  The newer versions of browsers tend to offer better     support    than older ones.
   

One should use latest browser to suport latest version of CSS>
        
Trying to make      a style sheet     that works in all major browsers can be a time consuming process of trial      and error,    requiring a larger initial time commitment to      test that the HTML document appears relatively correct in different browsers.      Even after all     that frustration, the webpage may not look perfect in     all browsers. To check the syntax, grammar, and possible     bugs in your CSS files,     you should     validate them.
        

Disadvantages of CSS:

• Inconsistent Browser Support
• Larger Initial Time Commitment
• Not Perfect
• Bugs