[Tutor] concerning help() function

[David]

Dear Tutors,

whenever I make use of the help() function, I have a good chance of
getting an error. I have not yet understood this tool very well.

Take the modules operator and random as examples. The former is
built-in, the latter not.
Do I wish to see the help files, I have to use a different syntax:

help(random)
help('operator')

I figured this by trial and error, and I am keen to find out when the
help() function is to be supplied with a string, and when no '' is
required. It certainly does not seem intuitive to me!

Many thanks,

David