After learning basic, grammatically correct Italian, it's important to also learn some slang. Most languages have a ton of slang, and Italian is no exception. Today I'll just discuss a few fun little Italian slang words.
If you see it written, in context, this one's not too hard to figure out. The n and g are reversed. But it's not just a typo, they really say "man-ya" in their slang, and it sounds different enough from "man-ja" that it won't be obvious if you hear it.
Se magna = I'm eating.
Whether you hear it spoken or see it written, the first inclination with this word is to understand it as "father", or perhaps as "the Pope". Neither of those is even close. If you look for a translation of the word "pappa", you'll find "jelly", and that's not it either. La pappa is slang for dinner.
Vado a fare la pappa = I'm going to make dinner.
If I thought "la pappa" was "father", it's easy to understand why I thought "la nanna" was "mother". Actually, at first I mistook it for "grandmother". And once again, that's not even close. La nanna means sleep, and it comes from "ninna nanna" which means lullabye.
Vado a fare la nanna = I'm off to bed.
Yeah, it's easy to see that this word probably means "accident", and I'm guessing that's where it came from. However if you hear someone exclaim accidente! they're not talking about an accident. It's acctually a light curse.
Accidente! = Damn!
cosa fai di bello
Literally, this phrase asks "what are you doing that's nice?" But that's far too literal and it misses the point. This is actually just a handy greeting, much like "what's up?" in English.
Cosa fai di bello? = What are you up to?
"Un sacco" is a bag, or a sack, and it's just a word that is used to mean "much" or "many", in much the same way as we use the phrases "a bunch" or "a lot" in English. This term un sacco is very common.
Un sacco di cose = a bunch of things.
"Madò" is short for "Madonna", also known as Mother Mary. The exclamation Madò is used in much the same way that an English speaker might use "Jeez!"
Madò, questa pioggia! = Jeez, what's with this rain?
And finally, the word "però" literally means "but". However però is a very common exclamation of disbelief.
Hai vinto una macchina? Però! = You won a car? No way!
That's just the tip of the iceberg, there are many more slang expressions in Italian, but these are all very common and understanding them is a great start.