It's time for our every-so-often password-related post.

This recent xkcd comic is instructive, and serves as a great visual illustration of AgileBits' original post on how to create a secure password.

When the comic began to get noticed, AgileBits wrote an updated, geekier version of that post, which has a much more detailed explanation of the science and math behind all this.

Of course, AgileBits makes 1Password, which is the most important piece of software that most people aren't using.  Buy it now and learn to use it, and you'll never have to think about this stuff again.