1) Never give any personal/private information to someone who called YOU out of the blue.
2) Never buy anything from someone who found you and pitched you on it.
3) You can just hang up! It's not rude to hang up on scammers.
Here are the six common scams in the article -- which is a short good read (just click on the picture).
1) Sweepstakes/lottery ("You have won! You just need to give us your banking info . . . ")
2) "Tech Support" ("We have detected a virus on your system, you need to give us access to your system so we can remove it . . . "
3) "Grandchild in Need" (Grandma, I've been arrested, send money . . . !")
4) Romance ("Send money and I'll visit you . . . ")
5) Social Security ("Give us your bank info . . . .")
6) Natural Disasters/Contractors ("We'll take care of everything, just give us your credit card number and we'll get started. ")