`git fetch` and `git pull` are both commands used to download new data from a remote repository. However, they serve different purposes and aren't interchangeable. 1. `git fetch`: This command brings your local copy of the remote repository up to date. It grabs any data from the target remote branch that does not already exist in your current branch. Importantly, it does not merge any of this new data into your working files. The primary use case for git fetch is if you want to see what's happened in the remote repository since your last pull without making any changes to your own files. 2. `git pull`: This command, on the other hand, does the job of both `git fetch` and `git merge`. It updates your current HEAD branch with the latest changes from the remote server. This means `git pull` not only downloads new data, but it also directly integrates these changes into your current working copy files. This has the potential to overwrite local changes. In general, if you simply want to view the updates from the remote repository without changing your files, use `git fetch`. If you wish to download the latest data and integrate it into your project, use `git pull`. For safety, especially when working in a team, preferring `git fetch` followed by `git merge` might be a good approach to avoid overwriting local changes.