Joking around is just joking around. You joke around with your friends and family. It's good comraderie. Tony Soprano jokes around with his best friend Artie Bucco (who is not a mob guy). There are plenty of mob guys joking around with mob guys. But then there's breakin' balls.
Breakin' balls starts with joking to someone or about someone concerning a perceived character fault, negative or embarrassing event at the expense of that person. The breakin' balls gets more personal and heated in an effort to illicit the biggest rise out of the other party. Sometimes it's done as starting out as the antagonizer just joking around at first. Sometimes it's done on purpose because party A dislikes or has a big grudge against party B. Breakin' balls rarely ends in just hurt feelings. It ends with at least a fight, and at most someone's life ending. The scene in GoodFellas is a prime example. But The Sopranos has the longest run of breakin' balls incidents.
Now, breakin' balls can occur in our normal, non-mob affiliated lives. A person you don't care for starts giving you a hard time, insulting you at your expense. When that happens, it's best to be polite, put on a brave face and perhaps walk away.
If you ever hear someone use the term "breakin' balls", you might want to be on your toes.
