Scrum is an Agile process that can be used to manage and control complex software and product development, wrapping existing engineering practices, including Extreme Programming and RUP, with the advantages of a simple implementation. Scrum significantly increases productivity and reduces time to benefits while facilitating adaptive, empirical systems development.

Test-Driven Development (TDD) is a software development technique consisting of short iterations where new test cases covering the desired improvement or new functionality are written first, then the production code necessary to pass the tests is implemented, and finally the software is refactored to accommodate changes.

Extreme programming (XP) is about project management and programming methodologies that are designed to enhance production. Extreme programming has some similarities with the Rational Unified Process (RUP) and some ways could be considered a very abbreviated version of the RUP with modifications.