i. Traditional Approach
In Traditional Approach of the System Development, activities are performed in sequence/phase. An activity/phase is undertaken only when the prior activity/phase is fully completed. The phases are: Feasibility Study, Requirement Analysis, Design or selection, Development /configuration, Implementation, and Post Implementation reviews.
ii. Prototyping Approach
The Traditional approach which is very formal may take very long time to analyze, design and implement a system. In order to avoid such a longtime, organizations are increasingly using Prototyping techniques to develop smaller systems. Prototyping, also known as evolutionary development, is the process of creating a system through controlled trial and error procedures to reduce level of risks in developing a system. This approach enables developers and users to understand and react to risks at each evolutionary level. Prototyping generally reduces the time to deploy systems using faster development tools. The goal of Prototyping approach is to develop a small or pilot version called a prototype of some parts or the whole system. A prototype is a usable system or system component that is built quickly at a lesser cost and with an intention to eventually modify or replace it a full scale and fully operational system.
iii. End User Development Approach
In this approach, the end user is responsible for the systems development activities, instead of the computer professionals. Generally, this approach is followed in a relatively small office or department having relatively inexpensive micro computers or office information systems. The number and the nature of system development activities followed the end users often differ from those found in the formal approaches such as the traditional approach. Therefore there is a possibility of development of inadequate specification requirements, adoption of inadequate standards and controls, lack of adequate specification and inadequate system testing.
iv. Top Down Approach
The Top Down approach assumes a high degree of top management involvement in the planning process and focuses on organizational goals, objectives and strategies. The logic here is that an information system needs to be responsive to and supportive to the organization‘s goal and objective. Therefore the development starts from the top to down.
v. Bottom Up Approach
This approach starts from the identification of the basic systems which is essential for the day to day business activities. The system such as payroll, sales order, inventory control, purchasing, etc. are developed first identifying their basic transactions, information file requirements and information processing programs.
vi. Systematic Approach
In this approach, information processing requirements are determined first and a search for suitable software and its evaluation is made. Once the software is identified, hardware is selected and then the information system is developed. Finally, the hardware and software are acquired or developed and the system is implemented.