Here’s something useful — and readable — from Lifehacker on encryption.
Encryption is a method of protecting data from people you don’t want to see it. For example, when you use your credit card on Amazon, your computer encrypts that information so that others can’t steal your personal data as its being transferred. Similarly, if you have a file on your computer you want to keep secret only for yourself, you can encrypt it so that no one can open that file without the password. It’s great for everything from sending sensitive information to securing your email, keeping your cloud storage safe, and even hiding your entire operating system.
The article goes on to give you a step-by-step guide on how to encrypt files using TrueCrypt. Read More Here. If you have trouble with this, you could drop by Noisebridge at 2169 Mission Street near the 16th Street BART station and probably get some help.