Re: Understanding GIT from an IBM i (RPGLE, CLLE, DDS) prospective

be reused so I move it to its own function. Meanwhile someone in another
branch changes something in that chunk of code. How does GIT automagically
merge stuff like that?

This is a good start: https://stackoverflow.com/a/14962580

I'm just trying to gather information about how it would work in their world
and maybe get a better understanding of what GIT is (Is it anything more
than source control) and what it does and doesn't do (does it automatically
compile programs once the branches have been merged or is that a manual post
merge step).

Git does no magic. 3-way merge (see above) works well in most cases, but conflicts do appear. The trick is that these conflicts occur in the developer's local copy of the code only, and should be only pushed to any main repository (from where others can pull changes) if the conflicts are resolved. Repositories don't accept pushes if they detect a conflict, and the client refuses to push until the developer resolves conflicts locally.

More info:
https://www.atlassian.com/git/tutorials/using-branches/merge-conflicts

The basic functionality of Git can be extended the way you describe (automatic compilation) using hooks. A lot of useful stuff is implemented like this (e.g. automatic testing of commits), but hooks really are just scripts that run at times when new code appears in a repository.