Computer Program Design

Program Development Cycle 

    The program development cycle, known as the software development life cycle (SDLC) or programming development life cycle (PDLC), is a structured and systematic approach to creating software developers follow to design, develop, test and deploy software. This cycle ensure that the software is developed efficiently, meets the desired requirements and is of high quality.

    Overall, the programming development cycle serves as a guide for software development teams, enabling them to create robust and reliable software applications while maintaining high standards of quality and and meeting user requirements.

    It is a set of phases and steps that are followed by problem solver to define, develop and maintain a program. Following are the 6 phases of program development development life cycle.

1. Review the Specification : The initial step involves a thorough examination of the project's specification and requirements. Stakeholders review and confirm a clear understanding of what the program is intended to accomplish.                                         
2. Informal Design : Following the specification review, developers create a high-level, less detailed plan outlining the overall structure and functionally of the program. this informal design phase serves as a blueprint for the subsequent detailed design and coding.                                                                                                                               
3. Formal Design : Developers create detailed technical specifications based on the informal design. This involves defining data structures in a more structured and comprehensive manner, providing a foundation for coding.                                               
4. Code and Compile : This phase involves translating the formal design specification into actual code using a chosen programming language. The code is the compiled into machine readable instructions for the computer to execute.                                              
5. Test  : Testing is a critical phase where the program is systematically evaluated to ensure it behaves as intended and meets specified requirements. Various testing methods, such as unit testing and system testing, are employed to identify and rectify any defects or issues.                                                                                                         
6. Maintain : Maintenance is an ongoing process where developers address bugs, make updates and adapt the program to changing requirements. Regular maintenance ensures the program remains effective, reliable and up-to-date throughout its life cycle. 

    Checklist for preparing a Task List

• What output  do you need to generate?
• What input do you have?
• What form will it be in?
• Will the program have a list of tasks that needs to be done repeatedly(LOOP)?   
• What are the other major tasks of the program?

    If it has repeated tasks :

• What will be done within it?
• What controls the loop?
• What need to be done before the loop?
• What needs to be done after the loop?

E.g. Let's prepare a cup of milk coffee. 

• What output  do you need to generate?

        - A cup of milk coffee

• What input do you have?

        - A cup, milk powder, sugar, coffee powder, water

• What form will it be in?

        - A empty cup, dry milk powder, dry sugar, dry coffee powder, boiled water

• Will the program have a list of tasks that needs to be done repeatedly(LOOP)?   

        - No

• What are the other major tasks of the program?

        - Take a empty cup

        - Add milk powder into the cup

        - Add coffee powder into the cup

        - Add sugar into the cup

        - Add boiled water into the cup

        - Stir 1 minute