The opposite would be "light traffic".
If a traffic light breaks most cities will assign a traffic cop to regulate traffic until the light can be fixed.
The traffic light was made in 1823.
I had to drive from Garner (which is essentially a southeastern extension of Raleigh) to Hammond, Indiana (which is right on the state line just before you enter the Chicago metro area) for traffic court. The drive was about twelve hours, but I also got there when traffic was light. You hit I80/90 when traffic isn't light, and it could add to your travel time significantly.
A traffic light you seen change to green
Yes. That is why they are called traffic lights.
your not so bright
The first traffic light was invented in December 10, 1868. The electric traffic light was invented in 1912. The Automatic Traffic light was invented in 1927.
Don't look; I'm changing
It is usually on the bottom of the traffic light.
J.P. Knight is the person who invented the traffic light. J.P. Knight invented the traffic light in 1868 in an effort to prevent fatalities on the roads.
inventor of the traffic light