A typical chain letter that would drop through your letterbox would ask you to make a number of copies of the letter and then pass them on to either a specific number of your friends or as many people as possible.  Common methods used in chain letters include emotionally manipulative stories, get-rich-quick pyramid schemes, and the exploitation of superstition to threaten you with bad luck if you "break the chain" and refuse to adhere to the conditions set out in the letter.

Chain letters by email are similar, but many have hidden dangers that raise them above the mildly irritating form that traditional chain letters take, plus the fact that they arrive by email and take no more effort to distribute than clicking a few buttons mean they are much more efficient than paper and envelope versions as its less trouble .   To large companies, Chain emails and other unwanted emails clog up the networks, consume disk space, and actually cost money to properly handle.

How does a harmless e-mail endanger my online security?

When you forward an email to everyone in your address book, you supply the next recipient with a list of email addresses of your friends. When your friends then forward it the email will contain the addresses of your friends along with the sender's friends and so on.

As each email is forwarded it collects large lists of email addresses, and competent computer criminals extract these addresses, and the relationships between the senders and recipients. The emails often have other information attached to them, for example the virus scanner you use, the company you work for etc.   These emails with lists of email addresses can easily drop into the "wrong hands", and do provide criminals with information.  To the spammer or conman, these emails identify people who are likely to fall for email scams, and their email addresses can become a target for a more specific scam.

Petition lists/competitions to win are another increasing scam, you receive an email inviting you to email your name, address, and telephone number to an email address to support a cause, and then send the email to your friends so they can do the same.  In the age of Identity theft,  if you give away too much information to a third party you may be susceptible to Identity theft.

Simple Steps to Identify a chain email.

• Any email that specifically asks or encourages you to distribute to your friends or promises good luck, vast amounts of wealth then its a chain letter.
• If it purports to warn you about scams or incidents that have happened recently and asked you to send it to everyone you know.
• A virus warning, purportedly from Microsoft or IBM, asking you to delete a file from your computer and pass the email on. Its a chain letter and its dangerous, and you will probably destroy something important if you delete the file. Buy a decent Anti Virus program if you are really concerned.
• Any email that asks you to visit a website and leave your details in a competition then send it to everyone you know. Think carefully is it dangerous? it's probably a chain letter - be safe hit the delete button and forget about it.

Jokes and funny stories .

There are things that don't fall into the above.

Think, could those images offend?  Could they be considered racist, sexist or any other "ist" then sending them to your friends work email could render them liable to disciplinary action, if they then forward them.  The contents of the email could contain viruses or Trojans.  Its best not to, but if you must forward them

• delete all other information from the email,
• delete the headers that contain other email addresses
• delete the footers that could identify where it has passed through,

Most importantly use the BCC (This is the Blind Carbon Copy) function on your email program, to include your distribution list, and send the email back to yourself.  This means that the email distribution list is not public anymore.