It is also possible that the package is on your system, but has not been
loaded. To see which packages are available for loading, look through
your computer's lisp directory (@pxref{Filename conventions}). The Lisp
-source to most most packages contains a short description of how they
+source to most packages contains a short description of how they
should be loaded, invoked, and configured---so before you use or
modify a Lisp package, see if the author has provided any hints in the
source code.