Command Stations are the heart of the DCC system. They receive commands from a throttle network (such as the Digitrax Loconet), process them, and decide if it needs to make a DCC standardized packet to send to the decoders on a DCC system.
That the first system that allowed independent control was the Lionel Electronic Control system, back in 1946? The first digital system was the Hornby Zero 1? That General Electric (which built full size locomotives) developed a command control system for model railroads in the 1960s?