Committing

git commit file1 file2 ... [-m msg]
Commit changes in file1, file2, etc., optionally using commit message msg or otherwise opening editor for commit message entry.
git commit -a [-m msg]
Commit changes made to all tracked files since the last commit, optionally using commit message msg or otherwise opening editor for commit message entry.
git commit --amend file1 file2 ... [-m msg]
Re-commit previous commit, including file1, file2, etc., using previous commit message or, optionally, a new one given by msg.