The C programming language (often, just "C") is a general-purpose, procedural, imperative computer programming language developed in the early 1970s by Dennis Ritchie for use on the Unix operating system. The first major program written in C was the UNIX operating system. It has since spread to many other operating systems. Although originally designed as a systems programming language, C has proved to be a powerful and flexible language that can be used for a variety of applications, from business programs to engineering. C is a particularly popular language for personal computer programmers because it is relatively small -- it requires less memory than other languages.

C++, originally named "C with Classes, is a high-level programming language developed by Bjarne Stroustrup at Bell Labs. C++ adds object-oriented features to its predecessor, C. C++ is a statically-typed free-form multi-paradigm language supporting procedural programming, data abstraction, object-oriented programming, and generic programming. C++ is one of the most popular programming languages. The C++ programming language standard was ratified in 1998 as ISO/IEC 14882:1998, and the current version of which is the 2003 version, ISO/IEC 14882:2003. A new version of the standard (known informally as C++0x) is being developed.

Computer-aided design (CAD), also known as Computer Assisted Design, is the use of a wide range of computer-based tools that assist engineers, architects and other design professionals in their design activities. It is the main geometry authoring tool within the Product Lifecycle Management process and involves both software and sometimes special-purpose hardware. Current packages range from 2D vector based drafting systems to 3D parametric surface and solid design modellers.

Computer-aided industrial design (CAID) is a subset of computer-aided design (CAD) that includes software that directly helps in product development. Within CAID programs designers have the freedom of creativity, but typically follow a simple design methodology: Creating sketches, using a stylus Generating curves directly from the sketch Generating surfaces directly from the curves

Callback

In computer programming, a callback is executable code that is passed as an argument to other code. It allows a lower-level software layer to call a function defined in a higher-level layer. Usually, the higher-level code starts by calling a function within the lower-level code passing to it a pointer or handle to another function. While the lower-level function executes, it may call the passed-in function any number of times to perform some subtask. In another scenario, the lower-level function registers the passed-in function as a handler that is to be called asynchronously by the lower-level at a later time in reaction to something. A callback can be used as a simpler alternative to polymorphism and generic programming, in that the exact behavior of a function can be dynamically determined by passing different (yet compatible) function pointers or handles to the lower-level function. This can be a very powerful technique for code reuse.

Computer Assisted Mass Appraisal (CAMA) is a generic term for any software package used by government agencies to help establish real estate appraisals for property tax calculations.

Careware, also known as charityware, is software distributed in a way that benefits a charity. Some careware is distributed free, and the author suggests that some payment be made to a nominated charity. Other careware includes a levy for charity on top of the distribution charge.

Casting Variable in computer programming simply means reassigning the type of a variable. When casting a variable from one type to another, all you are doing is telling the computer to use a different type to store the variable. For example, you declared a variable of type short. In most cases, that would mean that the largest positive value you could store would be 32,767. But somewhere in your program, you realize that you're going to have to do a calculation which could increase the value over this maximum. In this case, you need to perform casting variable.

cc65, an open source package under GNU General Public License, is a complete cross development package for 65(C)02 systems, including a powerful macro assembler, a C compiler, linker, librarian and several other tools.

CD Grabber, also known as CD ripper or CD extractor, is a piece of software designed to extract raw digital audio from a compact disc to a file or other output. CD grabber supports converting CD to WAV, the converter makes direct digital copies from audio CDs and saves them as WAV easily.

In computing, CD authoring or DVD authoring is the process of recording source material—video, audio or other data—onto a compact disc or DVD in a particular format.Authoring is commonly done in software on personal computers and workstations equipped with CD or DVD recorders. There are, however, stand-alone devices like personal video recorders which can also author and record discs.

CEA CNRS INRIA Logiciel Libre (CeCILL) is a Free Software license adapted to both International and French legal matters, in the spirit of and retaining compatibility with the GNU General Public License.

Celestia is an open source, 3D astronomy program for Windows, Mac OS X, and Linux created by Chris Laurel. The program, based on the Hipparcos Catalogue, allows user to display objects ranging in scale from artificial satellites to entire galaxies in three dimensions using OpenGL. Unlike most planetarium software, the user is free to travel about the Universe.