Rapid application development (RAD) is a software development methodology that uses minimal planning in favor of rapid prototyping. The "planning" of software developed using RAD is interleaved with writing the software itself. The lack of extensive pre-planning generally allows software to be written much faster, and makes it easier to change requirements.
Rapid Application Development (RAD) is a term originally used to describe a software development process first developed and successfully deployed during the mid-1970s by the New York Telephone Co's Systems Development Center under the direction of Dan Gielan. Following a series of remarkably successful implementations of this process, Gielan lectured extensively in various forums on the methodology, practice, and benefits of this process.
RAD involves iterative development and the construction of prototypes. In 1990, in his book RAD, Rapid Application Development, James Martin documented his interpretation of the methodology. More recently, the term and its acronym have come to be used in a broader, general sense that encompasses a variety of methods aimed at speeding application development, such as the use of software frameworks of varied types, such as web application frameworks.
Rapid application development was a response to processes developed in the 1970s and 1980s, such as the Structured Systems Analysis and Design Method and other Waterfall models. One problem with previous methodologies was that applications took so long to build that requirements had changed before the system was complete, resulting in inadequate or even unusable systems. Another problem was the assumption that a methodical requirements analysis phase alone would identify all the critical requirements. Ample evidence attests to the fact that this is seldom the case, even for projects with highly experienced professionals at all levels.
Starting with the ideas of Brian Gallagher, Alex Balchin, Barry Boehm and Scott...