Spam & Phishing
Think of Spam as telemarketing through email. In the same way that you receive those annoying calls at dinner, you can receive those annoying emails at work. Spam runs the full gamut of advertising including home financing, hair loss remedys, or even more embarrassing topics. Try as you may, there is no sure fire solution to getting rid of Spam.
Simply put, Phishing is an attempt to defraud the victim. Phishers look to trick users into divulging account information of some sort to gain access and steal what does not belong to them. This is a very creative form of social engineering. Be sure that you really are going to do what you think you're going to do before you do it.