Varnish Cache is an open source, state of the art web application accelerator. You install it on your web server and it makes your website fly. It really true, if you have a big website with huge visitors then Varnish Cache will be really a boon for you.
Even Facebook recommends and uses Varnish Cache to speed itself up.
So we are gonna see how to install and configure Varnish Cache on Ubuntu Operating system with Apache Web server. (This article is to install varnish on Ubuntu 10.04 but its almost the same for other versions of Ubuntu. The version of apache doesn’t matter .)