Testing is one of the most critical phases of the Software Development Life Cycle. It ensures that the software meets the specified requirements, functions as intended, and is free from bugs. This article dives deep into the testing phase, explaining the different types of testing—unit testing, integration testing, system testing, and user acceptance testing. We'll also explore how the testing phase fits into the larger SDLC framework and why skipping this step could lead to project failure and dissatisfied clients.