ABS means anti lock braking system.The ecu is able to sense if
any of ur wheel is locking.If it sense the tyre that is locking,ecu
will open up a valve to lessen the brake pressure to prevent it
from locking as locking up of tyre contribute to skidding and that
is very dangerous...
P.S---my mechnical knowledge is limited so do correct me if i say
something wrong.thanks a lot guys.