What is System Development Life Cycle

 System Development Life Cycle
System development life cycle is a conventional way to develop an information system. It consists of many steps and involves different persons. The steps of SDLC are as follows:

 Preliminary Investigation

Preliminary investigation is the first phase of SDLC. Its main objective is to identify deficiencies and requirements in the user's current environment. An important result of the preliminary investigation is whether the system to be developed is feasible or not. Feasibility is determined on the following parameters: Whether current technical resources or technology is available in the developer's organization or in the market that is capable of handling the user's requirements. Whether the system is cost-effective economically or financially. How effectively the user will operate this software once installed. The feasibility study report is produced at the end of this phase. A final acceptance of the proposed system is taken from the user. The next phase is started when the proposed system is accepted.

Requirement Analysis
In this phase, the current business system is studied in detail to find out how it works and where improvements are required. It includes a detailed study of various operations performed by the system and their relationship within and outside the system. The analyst and user work closely during the complete analysis phase. A detailed document is prepared at the end of this phase called requirement specifications.

 System Design
The requirement analysis phase provides the requirements of the system. The next phase is to design the new system to satisfy these requirements. The design phase states how a system will meet the requirements identified during the systems analysis phase as mentioned in the requirements specifications. Some activities performed during the design phase are as follows: Identification of data entry forms along with the data elements Identification of reports and outputs of the new system Design the form or display as expected in the system. This may be done on paper or on a computer display using any design tools. Identification of data elements and tables for database creation Procedures for deriving the output from given input The document produced at the end of this activity is called design specification. The detailed design specification is given to the programmers to start software development.

 Software Development
In this phase, the actual coding of the programs is done. Programs are tested using dummy data. Programmers also prepare the documentation related to programs. The documentation explains how and why a certain procedure was coded in a specific way.

 System Testing
After the programs are tested individually, the system is tested as a whole. During the system testing phase, all software modules are integrated and tested to ensure that they are running according to the specifications. Special test data is prepared as input for processing. The results are examined to ensure that they are correct.

System Implementation
In this phase, the developed system is installed for use. The following activities are performed before the actual usage of the system: User personnel is trained to operate the system. The data files needed by the system are constructed.

 System Maintenance
The system may become less useful if any change occurs in the user environment. The
software may be modified for its effective use. The activity of system maintenance may vary
depending on the scale of modifications and enhancements.

• Database Environment