Are Scrum and XP comparable things or are they used for different things

Question

Are Scrum and XP comparable things or are they used for different things? what is the main features of each of them? how do they overlap?

I've been reading about both XP and Scrum over the past weeks and something is vague about them for me. Scrum does have a definitive official rulebook but for XP I'm not sure where to look.

Answer 1

Probably the biggest difference is that you can be completely trained in scrum without even mentioning software. It is more about the process of choosing what software to write and when to write it rather than how.

Conversely, extreme programming is primarily about the how, and specifically recommends certain programming practices, taken to the extreme. Peer reviews are a good thing, so take that to the extreme and do pair programming. Tests are too often forgotten, so take that to the extreme and write them first with TDD. Long release cycles are problematic, so take it to the extreme by being ready to release every iteration. Integration is easier the more frequently you do it, so take it to the extreme and do continuous integration.

Since scrum doesn't say anything about the "how," a lot of scrum teams eventually adopt XP practices, so you will see a lot of overlap. At my company, some scrum teams are essentially indistinguishable from XP teams, where others are pure scrum, and others pick and choose where appropriate. For example, they might do TDD for new development, but not for maintaining legacy code.

I would recommend for any team to get trained in both, but to not try to worry about being "pure" one way or the other. Your team is going to work best when it adapts to find its own style.

Answer 2

To get started with XP, see extreme programming.

Both Scrum and XP are agile methodologies. As such, they have many things in common - such as a daily short meeting (stand up vs daily scrum) and approaches for dealing with customers. They also have differences. XP has some lower level practices such as pair programming as well.

I googled "scrum vs xp" and looked at the first few results. I like this one best as it covers some tangible examples of differences. You may read some of the others if interested. Do note that both XP and Scrum get customized rather than followed literally. So if a Scrum is X weeks, people may use X-1 weeks.