Fetch downloads information without changing your current branch
git fetch contacts a remote and downloads commits and updated references. It does not automatically merge those changes into your current branch.
Why fetch is safe
Fetching lets you inspect what changed before deciding how to integrate it. This is especially useful before rebasing or merging a long-running branch.
Fetch specific remotes or branches
You can fetch one remote or a particular branch. After fetching, compare your local branch with the remote-tracking branch to understand what changed.