The software development life cycle consists of six phases. Every software development cycle goes through a similar model consisting of these six steps. In order the steps include: requirement gathering and analysis, design, implementation or coding, testing, deployment, and maintenance.
All six steps are necessary in developing the best software possible and ensuring that it is going to run as smoothly as it possibly can. When all six steps are implemented it makes it a lot more likely that any bugs or problems that might arise will come to the attention of the developers so that they can fix the problem.