Man id says:
-n, --name
print a name instead of a number, for -ugG
-r, --real
print the real ID instead of the effective ID, with -ugG
Better say:
-n, --name
print a name instead of a number, for -u, -g, -G
-r, --real
print the real ID instead of the effective ID, with -u,
-g, -G
