How is a Turing Test defined? Turing Test definition taken from wikipedia:


  The Turing test is a test of a machine's ability to exhibit
  intelligent behavior equivalent to, or indistinguishable from, that of
  a human. In the original illustrative example, a human judge engages
  in natural language conversations with a human and a machine designed
  to generate performance indistinguishable from that of a human being.
  All participants are separated from one another. If the judge cannot
  reliably tell the machine from the human, the machine is said to have
  passed the test. The test does not check the ability to give the
  correct answer to questions; it checks how closely the answer
  resembles typical human answers. The conversation is limited to a
  text-only channel such as a computer keyboard and screen so that the
  result is not dependent on the machine's ability to render words into
  audio


But how is a Turing Test defined? 

What type of questions are considered to be so good that trick the human judge?

What and who defines a human judge suitable to be a judge? (for example if the judge is 5 year old wouldn't he be more easily tricked than a 50 year old computer scientist?)

All those chatbots are considered to pass the Turing Test? Most people are not sure if the chat bot is an actual bot or not.
Although Alan Turing is of course a very important computer scientist, the Turing test is only superficially related to computer science. It is more related to philosophy.

As long as machines exist people have wondered whether it is possible to construct a machine that can think. But to answer this question we must first answer the question what it means -- what is thinking? Turing tried to circumvent this philosophical problem by changing the question a bit: the goal is no longer a thinking machine but a machine which is indistinguishable from a thinking being.

The Turing test was intended as a thought experiment to make the reader think about (artificial) intellingence in some way, but it appealed to a lot of people. So people started to organize Turing tests for real, and if you're doing real Turing tests, then of course you need real rules. Last year the Turing test organized by the University of Reading attracted a lot of attention because, according to the rules fixed for that particular Turing test, one computer program beat the judges. See here for the press release.