Robot

Robot units are StarCraft units that consist entirely of mechanical components.

The Zerg do not have robotic units, and there are relatively few types among the Terrans (eg spider mines). The Protoss have an entire structure (the Robotics Facility) devoted entirely to produce robotic units.

Robots are vulnerable to a variety of effects (such as a Ghost's Lockdown ability) and are immune to effects that affect organic units (such as a Queen's Spawn Broodling ability).