latter for pushing a change to the origin when we run git push --set-upstream origin master an error message comes stating :
fatal: remote error:
You can't push to git://github.com/JuliaLang/julia.git
Use https://github.com/JuliaLang/julia.git

Isn't the problem that you don't have commit access to this repository, whatever protocol you use?

Okay, I don't understand, but if you are saying and have two like on your comment, I accept it.

The point he's making is that you don't have permission to push to the julia repo over any protocol, so changing the protocol doesn't help: most people — yourself included — will not be able to push to the repo. The only people who can are people who have commit bit and by the time someone has that, they've probably sorted out what protocols they need to use to be able to push things to GitHub.

The git protocol is very basic and should work for everyone, which is probably why I picked it — even if your local CA root certs are messed up it will work. However, it's not encrypted, so there is a slight risk that people could get man-in-the-middled. Of course, no git hashes will be correct if any content has been modified, but people might not check those. So the argument for switching to https would that it's more secure, which is probably a good reason to do it.