Why did you give that website my email address?

When you joined that social network, probably Facebook, did you give them my email address?  Why?  I didn't tell you that it was OK.

"Oh no", you say "I would never do that!"

Well, if you gave them the password for your email account, you just gave them 'my' email address, along with everyone else's email address in your address book.  Now the social network is spamming everyone in your address book.  While the spam is an invitation to join you on your social network, it is still spam.  And that spam goes to everyone more than once if the original spam is not accepted.

If you did give them your email password, (which has compromised your email account!) I highly recommend you get busy right away and change the email account password to something very secure so any hackers on the social network will not be able to steal your email account.