The Amazon Mechanical Turk (MTurk) is one of the suite of Amazon Web Services, a crowdsourcing marketplace that enables computer programs to co-ordinate the use of human intelligence to perform tasks which computers are unable to do. Requesters, the human beings that write these programs, are able to pose tasks known as HITs (Human Intelligence Tasks), such as choosing the best among several photographs of a storefront, writing product descriptions, or identifying performers on music CDs. Workers (called Providers in Mechanical Turk’s Terms of Service) can then browse among existing tasks and complete them for a monetary payment set by the Requester. To place HITs, the requesting programs use an open Application Programming Interface, or the more limited Mturk Requester site.

Requesters can ask that Workers fulfill Qualifications before engaging a task, and they can set up a test in order to verify the Qualification. They can also accept or reject the result sent by the Worker, which reflects on the Worker’s reputation. Currently, a Requester has to have a U.S. address, but Workers can be anywhere in the world. Payments for completing tasks can be redeemed on via gift certificate or be later transferred to a Worker’s U.S. bank account. Requesters, which are typically corporations, pay 10 percent over the price of successfully completed HITs (or more for extremely cheap HITs) to Amazon.[1]

Fascinating. It’s named after The Turk:

The name Mechanical Turk comes from “The Turk”, a chess-playing automaton of the 18th century, which was made by Wolfgang von Kempelen. It toured Europe beating the likes of Napoleon Bonaparte and Benjamin Franklin. It was later revealed that this ‘machine’ was not an automaton at all but was in fact a chess master hidden in a special compartment controlling its operations. Likewise, the Mechanical Turk web service allows humans to help the machines of today to perform tasks they aren’t suited for.

There’s also some criticism that Amazon Mechanical Turk constitutes a sort of virtual sweatshop.

Wikipedia: Amazon Mechanical Turk

Amazon’s Mechanical Turk page

See also: For Certain Tasks, the Cortex Still Beats the CPU