alt Hacker NewsObjects are your files. Underlying git is a content-addressable filesystem.
The objects are referenced by trees. A tree is just a directory.
The trees are then referenced by commits and/or tags into a DAG with named pointers into various parts of it (which are your branch and tag references):
https://git-scm.com/book/en/v2/Git-Internals-Git-Objects
Because it would be terribly in-efficient to have a bunch of loose objects, git periodically groups them together into packs. To save space, the objects are compressed against one another (delta compression) within the packs.
https://git-scm.com/docs/git-pack-objects
https://github.com/git/git/blob/master/Documentation/technic...
When pushing or pulling, the git transfer protocol basically enumerates what objects each side has so that it only needs to transfer the difference. On top of that, it delta compresses the objects on each side that aren't already grouped into packs against each other to save space.
https://github.com/git/git/blob/master/Documentation/technic...
Because git is an open-source project written by nerds, it shows you all of this information. Feel free to ignore it!
But if you really want to know, it's all documented both in the git book and git documentation directory, both linked above.
(Caveat: I'm working from memory and surely got some detail at least slightly wrong.)
Replies
The point is that if it's useless information for 99.9% of users, what's it doing in the UI?
Now explain this to an artist with very little programming experience beyond what they picked up from their coworkers.
I don't mean to be too glib, but some programmers have this decrepit idea that anyone working with computers should understand programming to be able to fully utilize them.
I worked in gamedev, and many of my colleagues were brilliant, but your comment would read as complete nonsense to many of them. That is the problem git has in the gamedev space. You're trying to manage teams of programmers, designers, sound engineers, gameplay specialists, producers...even c-levels. The parent comment to yours is right, to many many people who work on things that Lore could be useful for would find git to be gobblygook.
Respectfully, I think you're missing the point. The GP is not asking for an explanation (and could look that up from the Git docs) but commenting on how user-hostile it is. There's lots of software like this, which is so unfriendly that once you've learned the minimum of how to do something and verify it worked, you don't want to touch it any more unless you really need to.
CLI output should be in plain language and omit or minimize unnecessary detail absent a -verbose flag - for example, I'm just not interested in how many threads something took unless I'm working on it. As a user, I want to be focused on the task I'm doing, not on the perfromance of the tool.
Do you know what a rhetorical situation is? Do you understand that the parent was not actually seeking answers to these questions, but was using the questions themselves to make a point about the Git UI?
> Because git is an open-source project written by nerds, it shows you all of this information. Feel free to ignore it!
This is the type of attitude that kept most Unix tools quite user-unfriendly for several decades. What information to show the user, and when, are important design decisions to make. Just dumping it all on the user and making them wade through it is not doing the user a favour. Thankfully newer tools seem to be better about this, which has brought the Unix shell forward by leaps, even if there's still ways to go. (You can still make a conscious design decision that the info needs to be all there, and git is one of tools where that's at least somewhat justifiable, but a lot of the time the attitude is more like in the quoted text, that dumping out more info is always better.)