First, let us understand what git pull is:
The git pull command is used to fetch and download content from a
remote repository and immediately update the local repository to
match that content. The git pull command is a combination of
git fetch and git merge. git pull will download the content from
the remote repository. Once the content is downloaded, git merge will
merge the content to your local repository. A new merge commit will
be created and HEAD updated to point at the new commit.
Now that we know what git pull does, when we do
git pull origin master, it simply fetches a copy of the master
branch from the original repository, and merges it with the current
branch that you have checked out.
For more information, you can go to this link.
