$ fold --help
Usage: fold [OPTION]... [FILE]...
Wrap input lines in each FILE, writing to standard output.
With no FILE, or when FILE is -, read standard input.
Mandatory arguments to long options are mandatory for short options too.
-b, --bytes count bytes rather than columns
-s, --spaces break at spaces
-w, --width=WIDTH use WIDTH columns instead of 80
--help display this help and exit
--version output version information and exit
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Full documentation at: <http://www.gnu.org/software/coreutils/fold>
or available locally via: info '(coreutils) fold invocation'