I think it is fair to say that pull requests were made popular by GitHub and their brilliant implementation of the concept. Used in a strategic way, pull requests are a very powerful collaboration tool to have in your toolbelt – especially if you work in a team.
According to OSS Watch, a pull request “is a method of submitting contributions to an open development project“. But a pull request can be more than that. If you really adapt pull requests into your workflow, they provide a great space for teams to communicate, collaborate, educate and onboard new team members. This is now the norm in most open source projects, but many development teams – especially in the WordPress sphere – are not even using Git yet. If your team have not yet adapted Git (or another version control system) into their workflow, they are simply lacking the most basics of collaboration tools. The abillity to discuss and review code changes in a pull request is just one of many reasons to use Git, but it is definitely one that is big enough on its own.