It's not different. Typically there are no pauses, when all traffic lights at an intersection are red. In the UK, this happens in order to provide a period of time for pedestrians to cross while all the traffic is stopped.
In Canada and the US, at a standard N-S-E-W intersection (read crossroads with lights), all of the lights are red for only a split-second. Never much more than that. After that split second, in most cases, the following happens:
E-to-W and W-to-E traffic will be held on red lights. Simultaneously, N-to-S and S-to-N traffic will be held on red lights too. Also simultaneously, S-to-W and N-to-E traffic will be shown green flashing arrows pointing left, allowing them to turn across the intersection. This period allows cars to make left turns across the intersection with relative ease. All pedestrians are held at this stage.
After a while, the green flashing left arrows for the cars turning will turn to solid amber left arrows then disappear. At the same time as the amber left arrows disappear, the main S and N lights will go green, allowing N-to-S and S-to-N traffic to proceed straight. Pedestrians can now also proceed to cross the road, in the same direction as the cars. So cars turning right, must give way to a stream of pedestrians crossing the road who, previously, were waiting for the cars turning on the flashing green arrows.
During this time, in most cases, people who wish to turn left must wait because there is now a stream of traffic that they must cross. So these turners must now wait for a break in the traffic to cross (if there IS a break).
When the main lights turn amber, cars streaming from S-to-N and N-to-S should stop, if safe to do so, allowing the turning cars to clear the intersection. It is at this point that S-to-N and N-to-S amber-gamblers tend to squeeze the accelerator in order to get through the intersection, just as the waiting turners think they should be able to complete their turn.
All throughout this, cars can normally turn right on red in most states and provinces. More dangerous, congestion-causing and frustrating, is that when the flashing green turn arrows go amber and disappear, pedestrians are then shown the 'green man' to cross in the same direction as the cars are now travelling.
In a matter of a few seconds, the above will be repeated for E-to-W and W-to-E traffic.
If this all sounds confusing, try doing it at night, in the rain, in a city that refuses to use reflective paint but insists on using implausibly reflective tarmac, whilst driving on the wrong side of the road. Welcome to Vancouver...