To change a bit from whatever state it is in to the other

state; to change from 1 to 0 or from 0 to 1. This comes from

"toggle switches", such as standard light switches, though the

word "toggle" actually refers to the mechanism that keeps the

switch in the position to which it is flipped rather than to

the fact that the switch has two positions. There are four

things you can do to a bit: set it (force it to be 1), clear

(or zero) it, leave it alone, or toggle it.