No matter how many walls are placed around your machine, there is always a key for complete access: your password. There are countless programs that attempt to determine passwords, both by guessing common ones and by randomly generating possibilities and trying them all, or a combination of the two.

The best defense is a "strong password". A strong password is a combination of numbers, uppercase letters, lowercase letters, and, if possible, other characters. This makes the password nearly impossible to guess in a reasonable amount of time, and ensures that all the hard work you put into keeping your machine well-defended does not go to waste. The longer the password, the harder it is to guess.

Of course, as passwords get closer to random numbers and letters, they also get harder to remember. That doesn't mean that you have to fall back on a weaker password, though. You can m15peLL w0Rdz intentionally, or use a mnemonic device like a strong passphrase. Be sure to read the Microsoft article below for some very useful advice on this subject.

Always be sure to change your password if you think that there's a chance that someone else has seen it.

Protecting Your Password

Choosing a Windows Password

Choosing an OS X Password

Managing Your Columbia UNI and Password

Microsoft's Guide to Creating Stronger Passwords

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