Hi,
I think section 5.6 of v9.5.0 and 9.6devel can benefit from changing some occurrences of the word 'user' to 'role. Specifically, in
"For example, if joe is an existing user"
and
"The special "user" name PUBLIC can be used to grant a privilege to every user on the system.",
it is ambiguous whether "user" refers to any role, or a role with a LOGIN privilege, especially when you consider that CREATE USER is shorthand creating a role with LOGIN privileges.
Bests,
Johannes Choo