As you may have already guessed, ``joints.c'' contains a program written
in C.
On our computer systems, the file names of C programs end with the characters
``.c'' (a period and a lower-case `c'). This convention allows you
to just look at a file name and know what language the program was written in.
Many programming tools, including Emacs, know about this convention so that
they too can tell what language a program was written in. For this reason it's
important for you to follow this naming rule.
Now look at our example program again. Read the English text at the top of the
program and you'll discover that it solves a kinematics problem. (
Kinematics is the study of motion--position, velocity, acceleration--without
regard to the forces that cause motion.) We'll discuss the specific problem
that this program solves shortly.
Eric N. Eide
Hamlet Project
Department of Computer Science
University of Utah