One of numerous competing software development methodologies, such as Agile (SCRUM or Kanban), Scaled Agile (SAFe), Traditional/Waterfall, Rapid Application Development (RAD), Lean Software Development, Spiral, and others.

Resources:

Slug
agile

An intro for why I am interested in tuleap... (tuleap, part 1)

I became a huge fan of the Agile development methodology over a decade ago while working at Lumos Networks as a contract PHP developer. This is also where I learned Test Driven Development (TDD), and have much to thank Brian Johnston for bringing those skills into my toolbox, even after many years. And they say an old dog cannot learn new tricks.