Worker

These build your Structures and mine resources for you.

Overview
Workers are the units that collect Minerals and Vespene Gas, and construct buildings. They are the Drone (Zerg), SCV (Terran), and Probe (Protoss). All three types of workers cost 50 minerals to produce.

Workers are fundamental to economic and tech development, as they harvest resources and construct buildings. A good practice is to remember to constantly make Workers and Supply structures until you reach maximum saturation. Workers do not benefit from Attack Upgrades, only Armor Upgrades.

Construction
Each race's worker unit has a different way of constructing that particular race's Structures. SCVs must be present during the entire construction of buildings. The constructing SCVs may not be controlled during construction; construction must be completed, paused or cancelled to return control. SCVs may begin construction on most open ground.

Probes lay down warp beacons that result in a building after a period of time. The Probe may move to another task after setting the beacon, unlike SCVs and Drones. Probes may only set beacons inside the energy field generated by Pylons, with the only exceptions being the Nexus, Assimilator, and the Pylon itself.

When the Zerg require a new structure, Drones are sacrificed in the process of mutating into the desired buildings. With the exception of the Hatchery and Extractor, Drones can only mutate into structures if there is already enough Creep to fit the completed building.

Gameplay
Workers return 5 Minerals per trip from normal patches, and 7 Minerals per trip from rich patches. They return 4 Vespene Gas per trip. Each race has a Macro Mechanic to supplement their worker production. The Terran Merc Compound allows the call-down of SCVs. Protoss may use Chrono Boost to train Probes faster from the Nexus. Queens may use Incubate on Larva to make them hatch faster.