Scrum Framework
Scrum is a light weight framework that helps people generate value through adaptive solutions for complex problems.
Scrum Framework is built on empiricism and lean thinking.
Scrum employs an iterative, incremental approach to optimize predictability and to control risk.
As a framework, Scrum is not prescriptive, but only offers few elements and the rules associated with these elements.
Further Reading: A short summary of the Scrum Framework