This comic from xkcd.com touches on password strength and debunks a common myth – that of password complexity.
Most websites and workplaces etc are hot on password complexity to better secure your files and logins, but it would seem that it isn’t password complexity (or c0mpl3x1ty) that is important, but the length of the password.
This link, although containing some rather complex maths and other geeky stuff, gives you an idea of how long it would take to ‘break’ a password using a couple of different methods.
Here’s how long it would take to break a ‘complex’ password such as “xt15021a”:-
Much longer, isn’t it? So, when thinking up a password, it’s apparently much better, safer and easier to think of a four or five letter mnemonic or sentence that you’ll remember rather than a shorter password that’s made up of numbers, letters and other symbols.