Despite its namesake, spam is not a favorite Hawaiian breakfast ingredient, a pig byproduct, or my dad's favorite lunchmeat. That's SPAM, the compressed ham in a can made by the Hormel Foods Corporation.
No, spam is something completely different. And it's so important that it merits its own chapter in a computer security book. Lower-case spam is unsolicited commercial email or electronic junk mail.
It's those emails you receive in your inbox from people you don't know that advertise everything from religious T-shirts (see Figure 5.1) to adult websites (see Figure 5.2). Sometimes these ads are offensive. Other times they're stupid. Usually they are just plain annoying, especially because they arrive in huge volumes and rarely do they advertise anything you need. Don't you think spam would be less annoying if it offered to sell you a freshly baked pecan pie or a tasty piece of haddock? Spam never advertises anything good.
Figure 5.1. The site this spam links to offers a free "Wherever I go God is with me" T-shirt. It's odd, however, that the spammer has put 666 in the URL. Not a great marketing tactic when it comes to Christians.
Figure 5.2. This spam email features Alyssa, who has dark brown hair (isn't that blonde hair in the picture?) and black eyes (a little odd, too). Don't think she's interested in meeting you. The email clicks through to an adult website.