How many online services do you have accounts with? How many passwords? How many unique passwords? How many passwords can you remember?
For many reasons, most people have weak passwords & reuse the same password on different sites. PayPal says passwords aren't cutting it any more — time for something new.
http://www.macworld.co.uk/digitallifestyle/news/?newsid=3446582
How to construct a strong password
http://www.lockdown.co.uk/?pg=password_guide / security verify verification alphabetic numeric punctuation spaces eight characters remember random mix mixture upper lower case number numbers numerals punctuation symbols dictionary word English foreign alphabet secret reveal Fast Identity Online Alliance FIDO /