What do the letters mean when you do a git checkout of a branch?

[amurleopard]

Man page for git checkout: https://git-scm.com/docs/git-checkout
Man page for git status: https://git-scm.com/docs/git-status

When you do a git checkout you see different letters, it provides different short code status of the changes.

' ' = unmodified

M = modified

A = added

D = deleted

R = renamed

C = copied

U = updated but unmerged