LISP Programming Language

It has been more than 5 decades since the world has started its research on artificial intelligence. LISP is one such programming language which has given new means to get the actual results for the application of artificial intelligence. LISP is only the second language after FORTRAN to provide a platform for high level programming. Lisp has altered a big deal while its early stage. It has been developed in many dialects and it was proven to be very efficient to solve most of the major problems which were then faced in the field of artificial intelligence. It is a known fact that, now the field of AI is highly developed. But even then, Lisp continues to hold its own importance in high level programming.


Lisp is being developed for about half a century now. In 1958, John McCarthy invented this high programming language while in MIT. The name of Lisp is derived from the LISt Processing. John intended to use list processing in a programming language which can be used for artificial intelligence. The association of Lisp and AI has been coming along since the invention of Lisp. There are many features in Lisp which are capable of developing complex programs. John started writing programs which was initially bracketed ‘M-expressions’ and these notations were later changed into bracketed ‘S-expressions’.

There were many developments in the language after its primary release. Tim Hart and Mike Levin were responsible for implementation of the first Lisp compiler. It was written in Lisp and it introduced the mixing of compilation and interpreted functions which were possible freely.

Lisp was started using for the general purpose, after Daniel Edwards has introduced Garbage collection routines in this programming language. But that didn’t solve the problem completely as there were problems with the efficiency of the program. This has inspired the development of Lisp machines. These machines are skilled to run Lisp programs. Lisp machines were not a huge success though and they soon became obsolete in the hardware market.

In the mid 1990s, Common Lisp which was a major version of evolved Lisp programming language helped the language to regrow in the market. The common Lisp language is still has a profound usage in solving web problems.

Salient Features

Lisp programming language is responsible for setting up a platform for many languages to be derived from it. As mentioned before, it is a list programmed language. Everything depends on list of variables or objects here. It has some unique features which are completely different from its then counterpart FORTRAN. The following are some of the salient features with which Lisp is operated,

Atoms – Most of the programs which are run by lists are mostly dependent on their data structures. Lisp follows 2 types of data structures. Atoms are one of the major types of data structure. It is generally used as an identifier. In special cases it can also be used as numeric codes.

 Lists – List is another very important data structure. They can comprise the list of atoms or numeric constants or any of the above. It can also be the combination of lists and atoms.

 Uniform Representation – the representation of elements in the program is done uniformly. It follows a pattern which is systematic. This makes the execution of the program much easier. Each element is considered as data and the function of the element is interpreted as code.

 Garbage Collection – Garbage function is one of the vital features of Lisp. This leads to automatic memory management which is very important in general purpose programming. The user doesn’t have to free allocated dynamic memory manually as Lisp has in-built garbage collection.

 Functional Programming – there is not much of variable declaration. Arguments are computed by performing functions on them.

 Reliance on Recursion – This feature has helped the language to be very successful in its applications in artificial intelligence and in various other fields.


Lisp programming language is one of the most versatile programming languages available in the software world right now. It is mainly used in AI field. There are other platforms also which use Lisp but not to an extreme extent.

Some of the applications of Lisp are:-

  •  AI robots which are used for manufacturing and other purposes.
  •  Computer games and other media games.
  •  Defense system.
  •  Embedded knowledge based systems.
  •  Educating amateurs with functional programming pattern.
  •  Pattern recognition is also one of the important applications of Lisp.