The SDLC waterfall model is the most commonly used methodology in the software development industry for those organizations that still use traditional SDLC methodologies. Phase 1 - Requirements Analysis All requirements for the software are captured in a specific software requirement specification (SRS) document.
Phase 2 – Design Development teams will learn the requirements captured in the SRS document and then create the system design specifications (System Architecture, Flows, Hardware, Etc.).
Phase 3 – Coding (or commonly known as Build) The development team will use the system design document and start to develop the software (Data layers, Services, Procedures Etc.). The basic development cycle is to start with the units, modules that will integrate into advanced development phases to create the system.
Phase 4 – Testing The system that was developed in the coding phase is now delivered to QA teams so they can run "Functional" and "nonfunctional" tests. During this phase, testers will report software bugs that will need to be resolved by the Development Teams.
As you can see, this model is relatively simple. It is clear that testing happens only at the end, just prior to release. Now, if you not familiar with this approach you may get the impression that there is as much time for testing as there is for coding.
Note: Details of each phase will be written later.