Commits are done top your local files. When you are ready to sync those changes to the online repository(github), you do a Push. This will move all your local commits to the server. So I guess the apt term would be ’ Push’ . Because each Push can contain multiple Commits. However git never worry about ‘pushs’. For git, only the commits matter. If you look in n activity log in GitHub, it only mentions the ‘commits’ not the ‘pushes’
So
Syncing = Push
Each change = Commit
We use Git where we work, and usually I just tell the guys, ‘I have pushed that feature I was working on’. This is because I might have done several commits before the feature was complete.
Now ‘Merging’, it is only applicable when you have more than 1 working branch. Suppose you have a stable code base. Now you want two new features. YOu take care of one and another guy says he will do the otehr one. So each of you create your-own branches from the current master branch. You will work on these branches and push changes to your-own branches (just like how a tree branches out). At the end when each of you complete your work, you will merge your branch with the parent (master). And when both of you have merged your-own branches with the master, the master will have all the code:
master = master+branch1+branch2
This is called merging. This happens when you work in parallel, and I think this is the true power of git.
Git is pretty complex at first. But there are some nice tutorials out there which will give you a good idea.