Users are required to enter a safe password to secure their account.
There is no fixed list of rules.
The passwords are evaluated by strength estimator (zxcvbn) inspired by password crackers. Through pattern matching and conservative estimation, it recognizes and weighs 30k common passwords, common names and surnames according to US census data, popular English words from Wikipedia and US television and movies, and other common patterns like dates, repeats (aaa), sequences (abcd), keyboard patterns (qwertyuiop), and l33t speak.
To be accepted the password must get a minimum score of 2 on 4.
You can experiment and see your password score via this demo site https://lowe.github.io/tryzxcvbn/
