$ help command
command: command [-pVv] command [arg ...]
Execute a simple command or display information about commands.
Runs COMMAND with ARGS suppressing shell function lookup, or display
information about the specified COMMANDs. Can be used to invoke commands
on disk when a function with the same name exists.
-p use a default value for PATH that is guaranteed to find all of
the standard utilities
-v print a description of COMMAND similar to the `type' builtin
-V print a more verbose description of each COMMAND
Returns exit status of COMMAND, or failure if COMMAND is not found.
As a more general note, rather than just using
-h when you don't know what a command does, you should try:
type -a command
Which would in this case have told you it is a shell builtin.
is good for shell builtins. For other commands (and also for shell builtins, actually), try
-h is not necessarily the "help" option. If you don't know what a command does, that may not be a safe assumption to make. Safer is
(Common commands where
-h is a valid option but does not mean "help" are
du. All of these are informational only, but the assumption that
-h will only ever mean "help" is a dangerous assumption.)