It even offers “Plausible deniability” – if somebody forces you to give up the key by torture or threats, you can still be secure by giving up a false key to a false data, so to speak – you can read about it here – http://www.truecrypt.org/docs/plausible-deniability.php

The basic functionality of the software is to encrypt all your data including the OS, and asking for a password to boot up and decrypt in real time, or create a virtual volume where your secret data will reside. It is all clickable and easy to set up, so just give it a try.

Download