Compress PHP, CSS, JavaScript(JS) & Optimize website performance.
http://viralpatel.net/blogs/2009/02/compress-php-css-js-javascript-optimize-website-performance.html

We are using Wordpress as CMS for this blog, hence we decided to install WP-Super cache plugin for Wordpress to improve the performance. This plugin will create static HTML files from your blogs post and other pages and save them on web server. These HTMLs are served to client whenever consecutive requests are made. Hence this greatly improve the performance as it reduce PHP parsing and database connections. Bandwidth control is an important task to be followed when your traffic is increasing. With limited monthly bandwidth hosting, your site may run out of bandwidth and thus result in increase in down time. Hence it is very much advisable to compress your websites response with GZip and then serve it to client. Compressing output can significantly improve your websites performance by reducing the size sometimes upto 80%