Extreme Programming is a agile software development methodology designed to improve the quality of software and its ability to properly adapt to the changing needs of the customer or client. Similar to other Agile Methods of development, Extreme Programming aims to provide iterative and frequent small releases throughout the project, allowing both team members and customers to examine and review the project’s progress throughout.

Scrum can be considered as a framework for project management which can be applied to build a product quickly and with minimum complexities. A scrum team can use methods and practices from other agile flavors as per their needs. Scrum is not something curated specifically for software world problems and can also be used by other industry projects.

Key Differences Between Scrum and XP

Scrum	XP
Iteration is typically 2-4 weeks	Typically 1-2 weeks
Don’t allow requirements to change in Sprint	XP teams are much more amenable to change within their iterations. As long as the team hasn’t started work on a particular feature, a new feature of equivalent size can be swapped into the XP team’s iteration in exchange for the unstarted feature.
Scrum doesn’t prescribe any engineering practices	XP does, like Test Driven Development, Pair programming, Refactoring and so on
Scrum product owner prioritizes the product backlog but the team determines the sequence in which they will develop the backlog items. Example: it makes sense to work on a slightly lower priority item (let’s say #10 on the product backlog instead of #6) because the team will be working in thecode where #10 would be implemented.	Extreme Programming teams work in a strict priority order prioritized by customer.

Why is it called “Extreme?”

Extreme Programming takes the effective principles and practices to extreme levels.

• Code reviews -> pushed to extreme -> Pair Programming.
• Testing-> pushed to extreme -> continuous regression and unit testing.
• Design -> pushed to extreme -> do refactoring daily. And so on…