My classmates asked that question and the professor kept on talking about the probability of getting scammed but he's really against the whole crypto-currency movement so his opinion is biased.
So...here I am, asking for guidance...
Never trade something you do not know. Never trade with someone you never met. Never trust anyone you do not personally know, most of the time don't trust people you personally know neither. Bitcoin is a very dangerous thing when it comes to scamming, so when you deal with bitcoins or any other crypto, know that there is a big chance that the smaller an investment looks the bigger the chance for scam.
There have been huge amount of scams as well but if you look at the numbers the people who keep stealing couple hundred from many people have actually scammed more than people who scam tens of thousands of dollars. The big ones get arrested or sued and what not, small ones get away with it because they only steal couple hundred bucks from you and you do not follow through with it.