This installation description is for Ubuntu.

It is installed by default.

User name and email configuration (for all projects of that user).

git config --global user.name "Krzysztof Kowalski"

git config --global user.email k.kowalski@example.com

User name and email configuration just for that project.

git config --local user.name "Krzysztof Kowalski"

git config --local user.email k.kowalski@example.com