What is the "foo.1" file that Xcode creates in a command line tool?

Question

When I create a new Xcode project with the "command line tool" template, Xcode automatically adds a file with extension ".1" (e.g. Car.1 and main.m). What is the ".1" file?

Answer 1

It is the source file for the manpage of the new command line program, if you want to provide one. Normally you don't, so you can safely delete it.