Hopefully by now you know that a 20 character password made up of just letters is stronger than a 6 character password that is uses symbols and numbers too. Length plays a key role in the strength of a password. Passphrases are a great way to make long passwords that are easy to remember. There’s a good article on the 1Password blog that made the excellent point that though a simple sentence is very long, it might not be as solid as you think. For example, if your pass phrase is “twinkle twinkle little star”, that’s a pretty obvious string of words to put together. The linked post has some good ideas for mixing up your passphrase so that it’s still easy to remember but much harder to guess. If you want to get truly random, they also mention a method of rolling dice to generate completely phrases with completely random words. Mix that in with a few random characters to avoid a straight dictionary attack and you’ve to a pretty solid password!
However you make your password, please make sure that it’s strong, you change it often, and you don’t use the same password on multiple sites. Or if you only want to remember one really good password, check out a tool like LastPass.
PS. If you haven’t read the comic referenced in the image above, here’s a link to the full strip.