Jan 18, 2019

The Five Software Development Life Cycle Phases

Software must handle ever-increasing demands, and it's essential that every application has a tested and robust design to meet client expectations. Developers use a system of software development life cycle (SDLC) phases to provide a structured process for quality software, while working efficiently and keeping to deadlines. Whether you work as a Robotics Software Engineer or a mobile app developer, a firm understanding of the SDLC provides the basis for a project to be successful. Different organizations may use slightly different systems, but in general, there are five main software development life cycle phases.


The first step is conversing with the client to nail down the product requirements. A clear understanding of the end goal helps to maintain efficiency by reducing the risk of misunderstandings.


Having established the purpose of the product, it's time to complete the top-level design. The developers and technical architects plan how the software operates in order to achieve its goal, considering all of the necessary components and any third-party services. This step also includes defining which technologies to use, and setting a project length and budget. It helps to have clear documentation of a design specification for the client to sign off, thus ensuring the team doesn't waste time creating unwanted features, or producing something that doesn't meet with the client's expectations.


At this stage, the development team should all know what needs to happen, and it's time to implement the plan. Developers work with their programmers to create the code modules, databases, back-end processes, and user interfaces for the final application.


To ensure a quality product, a team of experts runs tests on the software to make sure it works as intended under different circumstances. The testers are looking for anything wrong with the system, including:

  • Bugs and errors, such as the system crashing unexpectedly
  • Failures resulting from high traffic
  • Lagging, slow responses, and operations that time out
  • Operations that return incorrect responses
  • User interface errors, such as buttons that don't respond or forms that don't submit
  • Poorly structured user interfaces that make it difficult to use the system

Errors identified in testing are fixed by the developers, who return the updated software to the testers for another round of testing. This continues until the testers are happy with the operational integrity of the software.


If the software passes the testing phase, it's ready for deployment. The development team rolls out the product to the client. A maintenance team monitors the new system and resolves unexpected issues.

Start Developing Yourself

The software development life cycle phases provide the methodology to improve the overall development process and the quality of the end result. Taking a Udacity Nanodegree program is a convenient way to learn more about this important methodology, and many other fundamental principles of software development, programming, and computer science, so you have the foundation of knowledge you need to develop your own career.