Reverse Turing test subject of the test involves reversing the roles of the real and control subjects. When a Turing test is applied to a mixed group of human and computer subjects, the computers are the nominal subjects. However, the humans are judged in exactly the same way, and so their Turing test scores can also be calculated. This is another way of viewing the situation described in the previous section. The term "reverse Turing test" has also been applied to a Turing test (test of humanity) that is administered by a computer. In other words, a computer administers a test to determine
Turing completeness one instruction set computer) and the ability to change an arbitrary amount of memory ("e.g.", the ability to maintain an arbitrary number of data items). Of course, no physical system can have infinite memory; but if the limitation of finite memory is ignored, most programming languages are otherwise Turing complete. In colloquial usage, the terms "Turing complete" or "Turing equivalent" are used to mean that any real-world general-purpose computer or computer language can approximately simulate the computational aspects of any other real-world general-purpose computer or computer language. Real computers constructed so far can be functionally analyzed like a single-tape Turing