Tuesday, May 11, 2010

History after 1950

A number of efforts have been directed toward further refinement of the definition of "algorithm", and activity is on-going because of issues surrounding, in particular, foundations of mathematics (especially the Church–Turing Thesis) and philosophy of mind (especially arguments around artificial intelligence). For more, see Algorithm characterizations.

Self-modifying programs

A computer program in execution is normally treated as being different from the data the program operates on. However, in some cases this distinction is blurred when a computer program modifies itself. The modified computer program is subsequently executed as part of the same program. Self-modifying code is possible for programs written in Machine code, assembly language, Lisp, COBOL, PL/1, Prolog and javascript (the eval feature) among others.

Programming

Computer programming is the iterative process of writing or editing source code. Editing source code involves testing, analyzing, and refining, and sometimes coordinating with other programmers on a jointly developed program. A person who practices this skill is referred to as a computer programmer, software developer or coder. The sometimes lengthy process of computer programming is usually referred to as software development. The term software engineering is becoming popular as the process is seen as an engineering discipline.

Computer program

A computer program (also a software program, or just a program) is a sequence of instructions written to perform a specified task for a computer.[1] A computer requires programs to function, typically executing the program's instructions in a central processor.[2] The program has an executable form that the computer can use directly to execute the instructions. The same program in its human-readable source code form, from which executable programs are derived (e.g., compiled), enables a programmer to study and develop its algorithms.
Computer source code is often written by professional computer programmers. Source code is written in a programming language that usually follows one of two main paradigms: imperative or declarative programming. Source code may be converted into an executable file (sometimes called an executable program or a binary) by a compiler and later executed by a central processing unit. Alternatively, computer programs may be executed with the aid of an interpreter, or may be embedded directly into hardware.
Computer programs may be categorized along functional lines: system software and application software. Many computer programs may run simultaneously on a single computer, a process known as multitasking