What is an 'epic' in the context of agile user stories?

An 'epic' in the context of agile user stories refers to a significant user story that is too expansive or complex to be completed in a single iteration or sprint. It often encompasses a larger piece of functionality that is broken down into smaller, more manageable user stories that can be individually developed and delivered. By identifying an epic, teams can simplify the process of planning, execution, and tracking of work as they divide it into smaller tasks.

This concept is vital for agile methodologies as it supports the iterative nature of development, allowing teams to prioritize and tackle components of an epic over time, thus maintaining flexibility and adaptability in their workflow. This breakdown is essential for enabling teams to manage their backlog effectively and ensure that they can deliver value incrementally.