Turing Complete Languages

• A programming language is said to be Turing complete if it has computational power equivalent to a Universal Turing machine (UTM) -

  "It can be shown that a single special machine of that type can be made to do the work of all. It could in fact be made to work as a model of any other machine. The special machine may be called the universal machine"

• Physically any such programming language is impossible to achieve since it requires unlimited storage ( Why ? ) . So , the term Turing complete languages applies to all those programming languages that would emulate a UTM if provided with unlimited storage.

• All general purpose programming languages are Turing complete ( C, Java, LISP, Haskell, Prolog etc ) . The non-Turing complete PLs are rare to find, for eg, machines that always halt, those languages in which it would be impossible to form loops. Also, not all programs solved by Turing complete languages can't be solved by programming languages with finite looping capabilities.

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