Pa has a small number of molecules and a majority of the molecules are on the surfaces. An Ultra high vacuum can gain pressure from .0001 to even lower pressures. There are many applications in using the vacuum systems. First would either be to hold, transport, or shape objects. A second application would be when packaging food.
Vacuum technology is used to remove the humidity from the food, helping to dehydrate the food.
Then there is another application called vacuum impregnation. Vacuum impregnation is a process that removes all the gases and humidity and replaces these with another material. A classic example of where vacuum impregantion is used is in the packaging of semiconductor components. A diode is a product of this process. A glass tube has all the humidity and gases removed than is replaced with either silicon or germanium.