simultaneous system

alternate system

flexible progressive system

simple progressive system

reduces right angled and rear end collisions

increases right angled and rear end collisions

reduces right angled collisions but may increase rear end collisions

reduces rear end collisions but may increase right angled collisions

Stop or red time of a signal is the sum of go and clearance intervals for the cross flow.

Go or green time of a signal is the sum of stop and clearance intervals for the cross flow.

Clearance time is generally 3 to 5 seconds.

The cycle length is normally 40 to 60 seconds for two phase signals.

to designate traffic lanes

in roadways meant for two way traffic

to indicate that overtaking is not permitted

to designate proper lateral placement of vehicles before turning to different directions

stop lines

turn markings

crosswalk lines

lane lines