The purpose of this License is to make a manual, textbook, or other written do-
cument \free" in the sense of freedom: to assure everyone the e®ective freedom
to copy and redistribute it, with or without modifying it, either commercially
or noncommercially. Secondarily, this License preserves for the author and pu-
blisher a way to get credit for their work, while not being considered responsible
for modi¯cations made by others.

This License is a kind of \copyleft," which means that derivative works of the
document must themselves be free in the same sense. It complements the GNU
General Public License, which is a copyleft license designed for free software.
We have designed this License in order to use it for manuals for free software,
because free software needs free documentation: a free program should come
with manuals providing the same freedoms that the software does. But this

License is not limited to software manuals; it can be used for any textual work,
regardless of subject matter or whether it is published as a printed book. We
recommend this License principally for works whose purpose is instruction or