The Internet is vast (currently boasting over 224,749,695 web sites and counting) and contains much that's good... and some that is bad.
The bad we're focusing on today comes in the form of emails that appear to be real but aren't. One type of bad email is called a phishing email. It looks like it comes from a reputable company like Paypal or your bank, and may even mimic the company's exact layout and contain it's logo, but it's actually from someone trying to get you to divulge your login credentials so that they can log into your account and steal your money.
Another type of bad email is one that spreads malicious and baseless urban legends, like the one that traveled the web claiming that Febreeze killed cats. Or the one warning women in hysterical terms that there were boogey men lurking in mall parking lots waiting to abduct them. Or the one claiming that Swiffer Wetjets kills dogs.
Don't even get me started on the ones who claim to be from a wealthy Nigerian who merely wants to deposit a staggering sum of money into your account for no rational reason!
Fortunately, for all the bad going on, there's an equal amount of good: if you want to know if something is a scam or a hoax all you need to do is look it up in a search engine like Google and you'll find out immediately. If you perform a Google search for "Swiffer Wet kills dog," for instance, you will see that the very first hit is from a site called Snopes.com. Snopes is a repository of researched scams and hoaxes, and it's authoritative. If Snopes says an email is bogus, it is. (Swiffer Wet Jets are not toxic to animals, by the way.)
Another site that documents hoaxes is museumofhoaxes.com. Between it and Snopes you should be able to find documentation and research on nearly every silly email you've ever received.
To become scam-proof remember first that no reputable company will ever ask you for your username and password in an email, period. And for everything else that seems as if it could be true, there are sites you can turn to that will set the record straight.
To protect yourself from scams, remember that anything that seems too good to be true, is, and for everything else use a search engine and look it up before you give it credibility. The Internet is the most vast, comprehensive collection of information ever and it's your responsibility to use it to educate yourself while you travel through it.
Here's hoping you escape April Fool's Day unscathed!