Q. What do you mean by Prototype?

A prototyping approach lay emphasis on the construction model of a system. Designing and building a scaled-down though functional version of a desired system is the process called as Prototyping. A prototype is a working system which is developed to test assumptions and ideas about the new system. It comprises working software which accepts input, performs calculations, produces printed or displayed information or performs other meaningful activities. It's the first version or iteration of an information system which implies an original model. Customer evaluates this model. This can be efficiently done only if data are real and situations are live. Changes are expected as system is used. This technique is useful when requirements aren't well defined. A prototype is typically a test model. It's an interactive process. It may begin with only new functions and be expanded to comprise others which are identified later. Steps of Prototyping process are:

• Identify user's known information requirements and features required in the system.
• Develop a working prototype.
• Revise prototype based on feedback received from customer
• Repeat these steps as required to achieve a satisfactory system.

Actual development of a working prototype is responsibility of a systems analyst. The difference between an actual information system and a prototype model is that a prototype won't include the error checking, input data validation, security and processing completeness of a finished application. It won't provide user help as in the final system.

However sometimes prototype can evolve into the product to be built. Prototype can be easily developed with tools of fourth generation languages (4GL's) and with help of Computer Aided Software Engineering (CASE) tools. Prototyping approach is a form of rapid application development (RAD).