Chain e-mail

A typical chain letter consists of a message that attempts to convince the recipient to make a number of copies of the letter and then pass them on to a certain number of recipients (either a predefined number or as many as possible). The "chain" is actually an exponentially growing pyramid (a tree graph) that cannot be sustained indefinitely. Common methods used in chain letters include emotionally manipulative stories, get-rich-quick pyramid schemes, and the exploitation of superstition to threaten the recipient with bad luck or even physical violence or death if he or she "breaks the chain" and refuses to adhere to the conditions set out in the letter. Originally, chain letters were letters one received in the mail. Today, chain letters are often sent via email messages, postings on social network sites, and text messages.

There are two main types of chain letters:

In the United States, chain letters that request money or other items of value and promise a substantial return to the participants (such as the infamous Make Money Fast scheme) are illegal.

Some colleges and military bases have passed regulations stating that in the private mail of college students and military personnel, respectively, chain letters are not authorized and will be thrown out. However, it is often difficult to distinguish chain letters from genuine correspondence.

The oldest known channel for chain letters is written, or printed, on letters on paper. These might be exchanged hand-to-hand or distributed through the mail. One notorious early example was the "Prosperity Club" or "Send-a-Dime" letter. This letter started in Denver, Colorado in 1935, based on an earlier luck letter. It soon swamped the Denver post office with hundreds of thousands of letters before spilling into St. Louis and other cities.

Chain letters take religious perspectives especially relating to Christianity. Often these letters originate from centers, claiming to have originated from the Pope, with the intent of persuading people to make copies of such letters. The content usually gives one or two examples of people, sometimes public figures who obeyed and were rewarded and others who disobeyed and suffered heavily, which may even include cases of deaths and of someone becoming a millionaire overnight. These types of letters will flourish for some days and will die out naturally, partly based on the economic realities of the people, and maybe many would also reason that if that was truly the original letter, then it cannot contain cases of people who had broken or continued the chain.

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Wikipedia