The waterfall model has been appropriated from the manufacturing and construction industry and is now used in the software industry. Both of these industries have a structured physical environment, and any subsequent changes after product delivery are virtually impossible.
During the beginning of the software-manufacturing industry, there were no formal software development methodologies, so this model was taken over.
The following is a depiction of the waterfall model:
The waterfall model implies the following phases in software development:
- Analysis of requirements
- Development (design and programming)
- Testing
- Verification
- Maintenance