> When you configure a git remote in .git/config, there’s this > +refs/heads/main:refs/remotes/origin/main thing. > > [remote "origin"] > url = git@github.

> When you configure a git remote in .git/config, there’s this > +refs/heads/main:refs/remotes/origin/main thing. > > [remote "origin"] > url = git@github.com:jvns/pandas-cookbook > fetch = +refs/heads/main:refs/remotes/origin/main > > I don’t really know what this means, I’ve always just used > whatever the default is when you do a git clone or git remote > add, and I’ve never felt any motivation to learn about it or > change it from the default. This is a refspec[0], and it tells Git the relationship between local references and remote references, defined in the pattern [+]<src>:<dest>. So, in this case, it defines the local head of main to refer to the remote branch main on origin. You could, for example, define all branches on local as linked to all branches on the remote with +refs/heads/*:refs/remotes/origin/*. An example of a real world usage of this was when we were migrating our repo between providers -- configuring the fetch field to link a different remote for different branch names kept things simple for our developers as we quietly moved branches to the new remote. It also configures the scope of a git fetch command, iirc, so you can restrict your fetches to only scopes that you care about (maybe your team has a branch name prefix/namespace that you can specify, so when you git fetch you only get things that are relevant and not some other teams' branches you don't need). [0]: https://git-scm.com/book/en/v2/Git-Internals-The-Refspec https://git-scm.com/book/en/v2/Git-Internals-The-Refspec