Spam basically is an e-mail message that is unwanted, usually to many recipients and from an unknown source. Spam is very cheap for the sender, but ends up costing receivers valuable time in opening, reading, and deleting such emails. A spammer is one who sends spam.

Different Types of Spam

• Hoaxes:
  Internet hoaxes are e-mail messages written with one purpose; to be sent to everyone you know.The typical e-mail hoax will have a fake warning of some sort, such as a new virus or the immediate need to boycott a company, with the encouragement to send this warning on to anyone on your mailing list. Spammers usually try every means available to make their lies believable. Never forward any "warning" on to others until you have done research and found it to be true through a reliable source such as Symantec Anti-Virus Research Center, Full Hoax Index .
  
  

• Chain Letters:
  Chain letters have the same purpose as the hoax messages but use a slightly different method of forcing you into passing them on to everyone you know. Chain letters generally offer luck or money if you send them on. They prey upon those who are greedy or naïve.