What is the difference between Agile and waterfall?

What is the difference between Agile and Waterfall is a common question. Agile is an approach to product development which aims to be adaptable and responsive to changes. It is designed to be used in environments which are subject to rapid change, such as software development. In Agile, work is planned and performed in an incremental and iterative manner, divided into multiple fixed timeboxes called sprints. Work is planned in advance only until the end of the next sprint which might be anywhere between 1-4 weeks. Agile emphasises adaptability and teamwork, and is based upon the core Agile principles.

In contrast, 'waterfall' is associated with the more traditional project management where a project is planned at the start, goes through a linear series of phases, each one only proceeding to the next one when certain conditions have been met. This makes waterfall project management less able to respond quickly to changes than Agile ones.