What are .1 files in /usr/src?

[William Michael Grim]

Hello!

I was curious, what are all the .1 files in /usr/src?  A couple examples
are /usr/src/bin/dd/dd.1 and /usr/src/bin/pax/pax.1.  Are these some sort
of files that are converted to man pages in some way?  If so, how is this
achieved?

Thanks in advance for the insight.

William Michael Grim
Student, Southern Illinois University at Edwardsville
Unix System Administrator, SIUE, Computer Science dept.
Phone: (217) 341-6552
Email: wgrim at siue.edu