1. System: These variables are available for every user in the system and stored in
[path]/etc/gitconfig.
Example: C:/Program Files/Git/etc/gitconfig
You can make git read and write from System by passing --system as option. It also requires you to have administration permissions.
2. Global: Global configurations are available for the current user for all the projects and stored in
~/.gitconfig or ~/.config/git/config
Example: C:/Users/Username/.gitconfig
You can make git to read and write from Global by passing --global option.
3. Local: Local configs are available for the current repository only and stored in
[gitrepo]/.git/config
Example: C:/Users/MyProject/.git/config
You can make git read and write from Local by passing --local option.
Create a local config
$ git config --local user.name "Local User"
# Create a global config
$ git config --global user.name "Global User"
# Create a system config
$ sudo git config --system user.name "System User"
to verify the origin of your configuration :
git config --list --show-origin
Also, its important to remember each level overrides values the previous level.
Priority:
Local > Global > System