$fold -w 3
what is your name
wha
t i
s y
our
na
me
$fold -b 3
fold: 3: No such file or directory
$fold -b3
what is your name
wha
t i
s y
our
na
me
$fold -s3
what is your name
wha
t
is
you
r
nam
e
$

fold - wrap each input line to fit in specified width

Reference/Source :
Debian manual for "fold" .