You don't have to have use e-mail much before you receive forwarded emails with chain letters, petitions, warnings and stories. And often they sound as if they could be true.

How can you tell if the story about a struggling premature newborn who was helped by the hug of her twin is true? How are you supposed to know that a story about another premature baby recovering after her three-year-old brother sang to her is not true? The hug really happened and helped, but there is no record of a singing sibling.

If Starbucks really did charge ambulance workers at the World Trade Center $130 for water, it is not inconceivable that Neiman-Marcus charged $250 for its cookie recipe. But, Neiman-Marcus has its cookie recipe up on their website and you can get it for free. Only after the e-mail about Starbucks was circulated on the Internet did Starbucks deliver a $130 cheque to the ambulance company, and its president, Orin Smith, called to apologise personally.

The most frequently forwarded e-mail of 2001, according to David Emery, a chronicler of urban legends, was the message in which the 16th-century seer Nostradamus predicted the terror attacks of September 11. Regardless of what you think of Nostradamus, the trouble was that Nostradamus never wrote the "prophecies" attributed to him in the e-mail about "Two brothers torn apart by Chaos". A college student wrote it. The e-mail was an urban legend.

What is an urban legend? Above all, it's a great story - hilarious, horrifying, sad, eerie, instructive or some combination of these qualities. Urban legends comprise the traditions, stories, and beliefs of ordinary people.

Urban legends arise outside of institutional channels of communication and are spread from individual to individual - traditionally by word of mouth, but more recently via new technologies, such as fax and e-mail.

Internet hoaxes, or a recently coined term "Netlore", refer not only to urban legends transmitted via e-mail, but also to various other sorts of misinformation spread on the Internet as well. Examples include chain letters and false computer virus warnings. Internet hoaxes and chain letters are written with one purpose; to be sent to everyone you know.

Most of the hoax messages play on your need to help other people. Who wouldn't want to warn their friends about some terrible virus that is destroying people's systems? Or how could you not want to help this poor little girl who is about to die from cancer? It is hard to say no to these messages when you first see them, although after a few thousand have passed through your mailbox you (hopefully) delete them without even looking.

Recently, there have been reports of spammers (bulk mailers of unsolicited mail) taking e-mail addresses from hoaxes and chain letters. After a few generations, many of these letters contain hundreds of good addresses, which is just what the spammers want. There are also rumours that spammers are deliberately starting hoaxes and chain letters to gather e-mail addresses (of course, that could itself be a hoax). So now, all those nice people who were so worried about the poor little girl dying of cancer find themselves the recipients of tons of spam e-mail.

But urban legends are not always false. Every now and then one of these incredible tales turns out to be true. If you want to check out some story that you want to believe, here are two Websites that track the amount of truth in the stories we all hear.

TruthOrFiction.com (www.truthorfiction.com) is a website where you can quickly get information about eRumors, warnings, offers, requests for help, and humorous or inspirational stories that are circulated by e-mail. Urban Legends Reference Pages (www.snopes.com) is an impeccably researched sited owned by David and Barbara Mikkelson who have been tracking and studying contemporary folklore on and off the Internet for many years.

In addition, most anti-virus companies have a web page containing information about most known viruses and hoaxes. You can also call or check the website of the company that produces the product that is supposed to contain the virus. Checking the PKWARE.com site for the current releases of PKZip would stop the circulation of the warning about PKZ300 since there is no released version three of PKZip. Without researching the factual claims made in a forwarded e-mail there's no 100 percent sure way to tell it if it's a hoax, but here you'll find common signs to watch for: If the message purports to give you extremely important information that you've never heard of before, or seen elsewhere, be suspicious.

Look for statements like `This is not a hoax' or `This is not an urban legend'. They usually mean the opposite of what they say.

Look for overly emphatic language, the frequent use of UPPERCASE LETTERS and multiple exclamation points!!!!!!! If the message seems geared more to persuade than to inform, be suspicious. Hoaxers are out to push emotional buttons.

Remember that a company cannot track how many times an e-mail message is forwarded, although they can track how many times a web page is clicked on. A company cannot know if you forward their e-mail message, so they cannot ever make "something terrific" or horrific happen if you do forward it.

Whatever their truth, urban legends and Internet hoaxes tend to express people's real fears and concerns. Vigilance must include making the effort to distinguish real threats from the bogus ones, so our efforts don't go to waste.