The Software Development Life Cycle $($SDLC$)$ refers to a methodology with clearly defined processes for creating high$-$quality software. in detail, the SDLC methodology focuses on the following phases of software development:

Requirement analysis

Planning

Software design such as architectural design

Software development

Testing

Deployment

The three major phases of testing include: unit testing, integration testing, and user testing.

Discuss why testing is a major step in the SDLC and why each phase must be completed before deployment.