Compress your web pages

When optimizing web performance, most consideration is given to reduce number and file size of images, CSS and JS etc., and less consideration is given to size of HTML being sent to browser, called “document size”. Optimizing document size can be very beneficial.

There are two ways you can reduce the document size
1. Reduce HTML
2. Compress HTML sent

1. Reducing HTML: Well its not easy for developers, but its good to consider during writing html. A good way to do it is to use DIVs instead of tables. If used correctly divs reduces the code to text ratio in document. Secondly avoid using inline css styles and java script. You can use external css and js files for this purpose.

2. Compressing HTML: The best way to reduce the document size is to send html in compressed form. Today most of the browser capable of receiving html in compressed format, un compress it on client side and display it correctly. This reduces the time spent and bandwidth usage between browser and server significantly. If you are working with PHP and apache it is really easy to compress HTML before sending to client. Most of the PHP installations have built in gzip library. You only have to use it. If you have static files or don’t want to use PHP or have static html files you can use apache module mod_deflate to compress html. Both of above methods use gzip compression.

How gzip Works
gzip compression works by finding identical strings within a html, and replacing those temporarily to make the overall size smaller. Its compression algorithm makes is very suitable to be used with html, css as they have repetitive tags and definitions. For example if our html has tag 100 times it will replace this tag during compression thus reducing the size significantly.