Supply

In StarCraft, each Terran player has two Supply counters - the first refers to the amount of supply being consumed by the player's units and the second refers to the amount of total supply available. The difference in the two numbers is the amount of supply that is still available for constructing additional units. Once the difference in the two numbers reaches zero, a player will not be able to construct any additional units. Hidden is a 200 point Supply max, the limit beyond which your production structures can no longer turn out units no matter how many supply production objects you create.

Here is a list of how much supply each unit takes:

1 Supply: SCV, Marine, Firebat, Medic, Ghost, Vulture

2 Supply: Goliath, Siege Tank, Wraith, Dropship, Science Vessel, Banshee

3 Supply: Valkyrie

6 Supply: Battlecruiser

8 Supply: Armed Nuclear Silo

A Supply Depot provides 8 supply, a Command Center offers 10 supply.