Hanoi is an awfully vivid city. Primarily due to infinite numbers of motorbikes that roam through the area. It is almost incredible how people manage to drive in this traffic.
Here are a few simple traffic rules translated to western:
Red light: it is advised you stop, but should you wish not to stop, you just need to pay attention and honk if some other vehicles come from the sides
One way street: a street with decreased chance of a vehicle coming from the other direction. DECREASED.
Roundabout: a funky construction where vehicles go around a pile of rock with a palm tree for no apparent reason
Pedestrian: a moving lively object that needs to be avoided as it can damage the motorbike disrupt to movement
Pedestrian crossing: everywhere