在Rails中验证用户输入

I'm developing my first rails application and I've met a necessity to check user input. For example, sometimes when a user create accout, he or she enters the data that hardly can be called appropriate. I've found gems to check the correctness of email and date of birth, and I would like to know, if there are similar gems for user's name and other fields. Particularly, I need one that can check for the use of filthy language. I'm already a bit tired of "AnalAvenger666"s on my site. Thank you. I'm developing my first rails application and I