Internet enthusiasts are all aware of unwanted intrusions that happended to the famous microblogging service in recent months. To provide better security, Twitter decides to block a list of 370 passwords like : zxcvbn and 123456 or even words like cookie, password and without surprise twitter.
For information, ideally to prevent piracy you have to choose a password with lowercase, uppercase, numbers and special characters. And of course to set a different password for each web service.
And people nowadays speak abut passphrases and not passwords.So the more longer is your access code, the more your account is secure.