There's a reason some sites ask for, or require, a password that contains both letters and numbers. The first column describes passwords. The other columns tell you how long it takes a hacker to figure them out. Don't make it easy for someone to figure yours out. Link
(Image credit: The Book of Joe)
If one site gets hacked, that password is useless for any other site. Just need to remember the one password ( hopefully complex )for the program.