A proposal for a test of a machine’s capability to perform human-like conversation. Described by Alan Turing in the 1950 paper “Computing machinery and intelligence”, it proceeds as follows. A human judge engages in a natural language conversation with two other parties, one a human and the other a machine, and both hidden by a curtain or screen. If the judge cannot reliably tell which is which, then the machine is said to pass the test. Put another way “We place something behind a curtain and it speaks with us. If we tell the difference between it and a human being then it will be AI” (Dimiter Dobrev, PC Magazine, Bulgaria, November 2000). It is assumed that both the human and the machine try to appear human. In order to keep the test setting simple and universal (to explicitly test the linguistic capability of some machine), the conversation is usually limited to a text-only channel.