The only thing you really need to internalize is that all git operations are entirely local on your machine, except clone/fetch/pull/push.
(Another useful thing to internalize is that git pull is really just git fetch followed by git merge. git fetch is the part that involves network activity, while git merge is entirely local on your machine. I can't remember the last time I've used git pull, actually...)
So when you're doing git log origin/master, you're not looking at the current state of the master branch on a remote machine. Instead, you're looking at what the state was the last time you did a fetch/pull/push.
This is extremely useful for being able to work remotely.
The only thing you really need to internalize is that all git operations are entirely local on your machine, except clone/fetch/pull/push.
(Another useful thing to internalize is that git pull is really just git fetch followed by git merge. git fetch is the part that involves network activity, while git merge is entirely local on your machine. I can't remember the last time I've used git pull, actually...)
So when you're doing git log origin/master, you're not looking at the current state of the master branch on a remote machine. Instead, you're looking at what the state was the last time you did a fetch/pull/push.
This is extremely useful for being able to work remotely.