Most of the coreutils documentation is available as info pages. (Try "info coreutils" at a command prompt). A version of this documentation is also available online at http://www.gnu.org/software/coreutils/manual/html_node/index.html (Note that the online version may not reflect the version of coreutils in this package.) There is also a frequently asked questions document available at http://www.gnu.org/software/coreutils/faq/coreutils-faq.html