Using the simulation speed tools, you can increase or decrease the spped at which time p asses, or stop it. It can be useful to pause the simulation while examining details of a town or constructing new areas. Speeding up the game can be used to quickly make time pass while waiting for resources to become available or for buildings to be built.
While the simulation is paused, time won't pass, but you can still move the camera, place objects, and view object details. At normal speed, a year in game will pass in about an hour. At the fastest speed, time will pass ten times more quickly.