"Man pages, some assert, are obsolete. They're old-fashioned,
they don't have a lot of neat modern features, and they're written
in nroff, an old and strange markup language.
"All of this is true; nonetheless, man pages are the primary
source of documentation for Unix-like systems, and have been for a
long time. The man program is installed as standard on pretty much
every Unix-like system ever shipped; competing formats may require
users to install and learn new, unfamiliar tools. Man pages are
well-suited to being printed without substantial effort; you don't
have to format them, you can just feed them to a printer.
Furthermore, everyone knows how to use more to read files..."