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Computer programming
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Computer programming

Computer programming is the art and skill of creating a computer program, a defined set of instructions in source code that a computer can execute. Creating programs has elements of art, science, mathematics, and engineering.

"There is no substitute for a working program"
--Herbert Simon, a founder of artificial intelligence and Nobel laureate

Table of contents
1 Programs versus algorithms
2 Programming languages
3 Software development
4 History
5 See also
6 External links

Programs versus algorithms

An algorithm is a description of how a program executes a finite operation. In a sense, an algorithm is an abstracted program. All but the most simple programs contain many implementations of algorithms, as a house is constructed by walls, doors, and floors.

Programming languages

Main article: programming language

A program is written in a programming language that is translated into machine language executable by a computer, although it is possible to write directly in machine code. Programs written in any programming language can be translated into machine language, and its human-readable notation, assembly language.

Programming languages can be of different programming paradigms and expose different levels of complexity to the programmer. So, each is suited to certain tasks.

Software development

Main article: software engineering

Software is a mass noun for computer programs and data. The accompanying documentation is also considered an essential part of the software, even though it doesn't involve any actual programming.

Creating software involves:

  1. Recognizing the need for a program to solve a problem.
  2. Planning the program and selecting the tools (including hardware platforms, languages, databases, browsers, development kits) to solve the problem.
  3. Writing the program in the programming language of choice.
  4. Translation: translating the human-readable source code into either machine-readable executable code, which is done by compilers, assemblers or other tools, such as interpreters, which directly execute source languages (such as SQL, and scripting languages) at a higher level than libraries of machine code. In metaprogramming, programs are created which can generate the source code for other programs.
  5. Testinging the program to make sure it works; if not, return to step 3 (see code and fix).
  6. Documentation, deployment and delivery

These steps are collectively known as software development. The skills required to be a coder require the ability to mentally translate concepts of the first step to expressions in the target programming languages.

A revision control system for source code is a valuable resource for a programmer. It facilitates the reversion of changes, and the comparison of different methods used in the code.

History

Hero of Alexandria in the first century invented automated theatres that used analogue programming to control the puppets, doors, lights, and sound effects.

Ada Lovelace, daughter of Anabella and Lord Byron (the poet), was the first recognised computer programmer. Anabella gave her love of mathematics to Ada, who after meeting Charles Babbage, translated and expanded a description of his analytical engine. Even though Babbage never completed construction of any of his machines, the work that he and Ada did earned her the title of the world's first computer programmer, see Ada Byron's notes on the analytical engine. The Ada programming language is named for her.

One early programmer known to have completed all the steps for unaided computation, including compiling and testing, is W.J. Eckert. This man's work predated the rise of computer languages, because he used the language of mathematics to solve astronomical problems. However, all the ingredients were there: he operated a computing laboratory for Columbia University with equipment provided by IBM, complete with a customer service division, and special purpose engineering consultants, in New York City, in the 1930s, using punch cards to hold the intermediate results of his calculations, and then formatting the punch cards to control the printout of the answers, just as in the work for the census decades earlier. He even had debugging techniques such as color coding, cross-footing, verifying and duplicating. One difference between Eckert and today's programmers is that the example of his work influenced the Manhattan project. His work was recognized by astronomers from Yale University Observatory, Princeton University Observatory, U.S. Naval Observatory, Harvard College Observatory, Student's Observatory of the University of California, Ladd Observatory of Brown University and Sproul Observatory of Swarthmore College.

Alan Turing is often considered the father of computer science, and by proxy, programming. He was responsible for helping design and program a computer to break the German ENIGMA code during World War Two.

See also

External links