To move the bit pattern stored in a register so that either the least or
most significant bit is at the appropriate end of the register. This is
analogous to the similarly named process used in typesetting and word-processing
systems to achieve uniform vertical edges to pages or columns of print. Some
serial printers used with word-processing systems have a built-in justify
facility. The space between words and/or letters is increased until the printed
line fills the distance between the margins.