Many of Amsterdam's major streets are composed of several parts. The bikes lanes, the car lanes and the tram lane. It goes like this: bike lane, car lane, tram lane (usually 2 tracks), car lane and bike lane. There are 3 traffic lights or crosswalk lights. One for each of the car lanes, and one for the tram lane. There are pedestrian islands next to each light.
I observed (in horror) as a woman with a small child took off from the curb trying to beat the lights. The traffic from the other side of the intersection was already moving when she reached the second (the tram) island. Thank god, her husband, who was still on the curb with the other child, yelled STOP, and she did, or she would have barreled into oncoming traffic.
Also to be noted, many drivers here hit the gas like the start of Indianapolis 500 as soon as the light changes. And the bicycles are often looking at a bicycle traffic light, so just watch out for them. And sometimes, most times, they will chose to disregard their traffic light.
Some intersections have no lights or signs. You just have to pay attention.