Inspector, supervisor; comptroller, person in a business or company who is responsible for checking and handling financial matters (such as expenditures, etc.), chief accountant of a company, person in charge of the accounting activities in a company (Finance)

A device that other devices rely on for access to a computer subsystem. A disk controller, for example, controls access to one or more disk drives, managing physical and logical access to the drive or drives.
One who is in control; hardware device that manages a particular physical device (Computers)