Some signs prohibit parking while others prohibit stopping and parking. It sounds simple but are you sure you really know the difference between stopping and parking? Here is a short explanation that could be useful:
Your vehicle will be considered "stopping" only if you stop for the purpose of getting people in or out or when loading or unloading goods.
The duration of the stop is actually not taken into account in the difference between stopping and parking. If you load/unload goods, your vehicle will always be considered as stopped even if it takes you more than an hour.
The highway code indicates that the stop is found for a vehicle that does not stop longer than necessary to perform the loading/unloading or in/out of people. Once you have finished what you stopped for, your vehicle will be considered "parked".
Your vehicle will be considered "parked" if you stop longer than necessary for loading/unloading or boarding/disembarking.
So even if you stop for less than 5 minutes for any other reason, your car will be considered "parked" and not "stopped".
This also applies if you stay in your vehicle, whether to answer a phone call, consult a map/GPS or simply waiting for someone.
Also note that parking signs do not apply to disabled vehicles.
And of course, when you are stopped at a red light or in traffic, your vehicle will not be considered "stationary" or "parked".