NOTE: Provided parameters will be filtered out by partial matching regular expression. Rails adds default `:password` in the appropriate initializer (`initializers/filter_parameter_logging.rb`) and cares about typical application parameters `password` and `password_confirmation`.
### Good Passwords
INFO: _Do you find it hard to remember all your passwords? Don't write them down, but use the initial letters of each word in an easy to remember sentence._
Bruce Schneier, a security technologist, [has analyzed](http://www.schneier.com/blog/archives/2006/12/realworld_passw.html) 34,000 real-world user names and passwords from the MySpace phishing attack mentioned [below](#examples-from-the-underground). It turns out that most of the passwords are quite easy to crack. The 20 most common passwords are:
It is interesting that only 4% of these passwords were dictionary words and the great majority is actually alphanumeric. However, password cracker dictionaries contain a large number of today's passwords, and they try out all kinds of (alphanumerical) combinations. If an attacker knows your user name and you use a weak password, your account will be easily cracked.
A good password is a long alphanumeric combination of mixed cases. As this is quite hard to remember, it is advisable to enter only the _first letters of a sentence that you can easily remember_. For example "The quick brown fox jumps over the lazy dog" will be "Tqbfjotld". Note that this is just an example, you should not use well known phrases like these, as they might appear in cracker dictionaries, too.
### Regular Expressions
INFO: _A common pitfall in Ruby's regular expressions is to match the string's beginning and end by ^ and $, instead of \A and \z._
