This basic Internet scams primer appeared on The Next Web today. It goes over four (five if you include the Nigerian Prince scam) methods scammers use to trick their victims, concentrating on email as the vector of choice to reach their marks. Focusing on email makes sense; many, if not most, malware infections come from email attachments and links to web sites containing malicious code.
Prevention of malware infection starts with wariness toward every email that comes in. Malware can relatively easily be prepared to refer to you by name, appear to come from someone you know, or take on the exact outward appearance of an email from a reputable source. Usually, the giveaway is that the email contains an unnecessary attachment, or links to a web site other than the one it appears to be coming from (determine where links go by hovering over them with your mouse; the destination address will appear in the status bar on all major email programs).
The linked article isn’t exactly news, but it’s definitely worth a read as a reminder to be careful with email links and attachments.