title = Add new files to the index cards = add [description] In the index, we can prepare what will be in the next commit. Initially, the index will be empty, and all files are untracked. If you have a file, and you want to have it in the next commit, use `git add`! [setup] echo a > a echo b > b echo c > c [win] # Add all three files to the index. test "$(git diff --cached --name-only | wc -l)" -eq 3