Whenever we use man command it opens the manual corresponding to the command(if exists). Operations on it are almost same as that of the less command(like search forward using / or backward using ? or browse forward using d etc). I am just curious whether man command internally invokes less command to display the manual contents?
I would like to complement Ignacio's accepted answer.
Even the man utility has a manual that can be displayed by the man utility: man man.
The part answering your question:
Controlling formatted output
-P pager, --pager=pager Specify which output pager to use. By default, man uses less -s. This option overrides the $MANPAGER environment variable, which in turn overrides the $PAGER environment variable. It is not used in conjunction with -f or -k.