The development methodology in software engineering is a framework that is used to structure, plan, and control the process of developing an information system. The two methodologies we use are Waterfall, and Agile (which is often implemented using Scrum). Both are usable, mature methodologies and having been involved in software development projects for a long time.

The Agile Methodology

Agile software development uses iterative development where requirements and solutions evolve via collaboration between the organization and their customer. Agile processes fundamentally incorporate iteration and the continuous feedback that it provides to successively refine and deliver a software system. It also encourages rapid and flexible response to change.

For Agile development, we often use Scrum which is designed for development teams of between three to nine members who break their work into actions that can be completed within time-boxed iterations, called sprints (30 days or less, most commonly two weeks) and track progress and replan in 15-minute stand-up meetings, called daily scrums. Each sprint has a running list of deliverables, planned at the start of the sprint.
Deliverables are prioritized by business value as determined by the customer. As sprint is completed team should do a sprint review and retrospective meetings, in the sprint retrospective two main questions are asked: What went well during the sprint? What could be improved in the next sprint?

The Waterfall Methodology

Waterfall is a linear approach to software development. In this methodology, the sequence of events is something like:

1. Gather requirements
2. UI/UX Design
3. Implementation
4. QA
5. Submission
6. Maintenance

In a true Waterfall development project, each of these represents a distinct stage of software development, and each stage generally finishes before the next one can begin.