Web developers and web designers commonly face the challenge of making sure their web pages look correct in various browsers. Different browsers like, IE, Firefox, Safari and Opera can possibly render the same (html) web page quite differently.

To illustrate, here’s an example…

Firefox see the <hr /> tag and goes “Hey! that’s a <hr /> tag it should be displayed as a 1px thick horizontal line.”

on the other hand…

IE sees the same <hr /> tag and goes “Hey! that looks like a <hr /> tag, i think i will display it as a big fat 20px thick horizontal line… just for fun!”

So who’s displaying it correctly? Should the <hr /> be 1 px or 20 px thick?

There no absolute right and wrong, but if there was a standard way in which it was to be displayed that would be good -_-.

W3C to the rescue! Well… W3C is an abbreviation for “World Wide Web Consortium” - The World Wide Web Consortium is the main international standards organization for the Internet that define these guidelines for everyone.