The most basic methodology in software engineering is the Waterfall model. It’s a linear approach that follows a sequential order of phases, with each phase being completed before moving on to the next. The phases include requirements gathering and analysis, design, implementation, testing, deployment, and maintenance. The Waterfall model is straightforward and easy to understand, making it ideal for small, straightforward projects with well-defined requirements. However, it’s less flexible and less suited to more complex projects with changing requirements, as it does not allow for iteration or adaptation during the development process. Nonetheless, the Waterfall model remains a useful framework for understanding the software development process and it’s still used today in certain situations.