There is no man or info page for "command" on Ubuntu, I guess it's just a bash builtin ("which command" doesn't find it). "which" has a man page though.
$ 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.
Options:
-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
Exit Status:
Returns exit status of COMMAND, or failure if COMMAND is not found.Or just cranked-up a search engine.
So thanks for that.
Not to mention that most distributions completely ignore it and don't populate it with a program's info documentation -- even when such exists.
And, being GNU projects, Bash and `info` generally come hand-in-hand.