You’re not a silly person. Using git as a backup mechanism can be attractive, and despite what other folks have said, git works just fine with binary files. Read this page from the Git Book for more information on this topic. Basically, since git is not using a delta storage mechanism, it doesn’t really care what your files look like (but the utility of git diff is pretty low for binary files with a stock configuration).
The biggest issue with using git for backup is that it does not preserve most filesystem metadata. Specifically, git does not record:
- file groups
- file owners
- file permissions (other than “is this executable”)
- extended attributes
You can solve this by writing tools to record this information explicitly into your repository, but it can be tricky to get this right.
A Google search for git backup metadata yields a number of results that appear to be worth reading (including some tools that already attempt to compensate for the issues I’ve raised here).
etckeeper was developed for backing up /etc and solves many of these problems.