Rapid Application Development: Methodology, Concepts & E-Commerce

Introduction: RAD Definitions

Information technology has become an increasingly common presence across most domains of life. The business sector uses it for various purposes, such as increasing shareholder value, improving customer satisfaction, consolidating market position, and registering higher profits. A relevant strategy used to meet these goals is RAD, or Rapid Application Development, which is most commonly used within web-based applications destined for online commerce. This paper begins with a short presentation of the methodology and the concepts involved, examines its application in e-commerce, and concludes with an overview of RAD's advantages and limitations.

The introduction of Rapid Application Development (RAD) in the early 1990s—James Martin, in 1991, is generally credited as the scientist who introduced it—marked an essential phase in software development history. RAD increased the speed with which applications were developed while also improving their capacity to better fit customers' requirements. Additionally, the development process could be changed and adapted along the way, which made for a very flexible development structure.

The RAD methodology is generally defined as "a software development process that allows usable systems to be built in as little as 60–90 days, often with some compromises." The RAD methodology is based on three essential elements:

Prototyping relies on the creation of deliverable prototypes of the final product, which can then be gradually refined as feedback from customers and end users is obtained.

Iteration implies continuous improvement and development based on the refinement of previously obtained prototypes.

Timeboxing is the applied managerial technique that coordinates the previous two elements and ensures that the final product is delivered on time and to the required standards.

RAD vs. Structured Systems Analysis and Design Method

Prior to Rapid Application Development, the software development industry had been dominated by non-agile processes, including the Structured Systems Analysis and Design Method (SSADM) and several Waterfall models. The SSADM was a static development framework based on logical data modelling or data flow modelling.

The SSADM also included several strictly determined development stages: analysis of the current system prior to actual development (known as the feasibility stage), a descriptive outline of the business specifications, followed by a detailed business specification process, a logical system specification stage, and the physical design of the final product.

The SSADM methodology was part of a larger software development framework referred to as Waterfall models, mainly because one stage preceded the next and each subsequent stage was dependent on the outcome of the previous one. No secondary stage could be completed until the previous primary stage was fully finished. There was a strict dependency between all development stages in the software product's lifecycle. The concept of sequential development is central to Waterfall models and all frameworks based on this concept.

The main problem that Waterfall models introduced was that clients' feedback could generally not be incorporated into the final product until it reached the last stages of development. By that time, several complications could arise: (1) the client's specifications may have changed, especially if development took a long period of time, or (2) the client's input would have implied significant changes, which in turn increased financial and human resource costs.

The agile software development methodology emerged in an attempt to solve these problems. With a higher degree of open collaboration and greater flexibility and adaptability, the agile approach encouraged communication both within the development team and with the customer. This meant that requirements could be better matched to the product, and the final deliverable—shaped by changes made along the way—more accurately reflected the customer's needs. Rapid Application Development fit precisely within this methodological framework.