Like most languages, Italian boasts quite a variety of bad language, and Italians, as I have mentioned elsewhere in this blog, are not too shy about resorting to it. Knowing what is OK, and what is not, can help those learning Italian avoid causing themselves some embarrassment.
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Stop translating in your head and start speaking Italian for real with the only audio course that prompt you to speak.
If you would like to know more, and are not offended by strong language, then About.com’s Italian Slang Dictionary–Adult Section has a comprehensive selection of language that would not be acceptable to your mother, depending where you are from. I believe knowing such language can be quite useful, in that it can help you to understand when someone is saying nasty things about you, or your actions, and it can help you avoid making a few faux pas.