Actually Git stores configuration options in three separate files, which lets you scope options to individual repositories, users, or the entire system:
repo/.git/config – Repository-specific settings
~/.gitconfig – User-specific settings
This is where options set with the --global flag are stored.
git config --global user.name "Love"
git config --global user.email love@example.com
$(prefix)/etc/gitconfig – System-wide settings.