Overhead may be: *

Overhead (business) In business, overhead or overhead expense refers to an ongoing expense of operating a business. Overheads are the expenditure which cannot be conveniently traced to or identified with any particular revenue unit, unlike operating expenses such as r ...

, the ongoing operating costs of running a business *

Engineering overhead In engineering, some methods or components make special demands on the system. The extra design features necessary to meet these demands are called overhead. For instance, in electrical engineering, a particular integrated circuit might draw large ...

, ancillary design features required by a component of a device **

Overhead (computing) In computer science, overhead is any combination of excess or indirect computation time, memory, bandwidth, or other resources that are required to perform a specific task. It is a special case of engineering overhead. Overhead can be a decidin ...

, ancillary computation required by an algorithm or program **

Protocol overhead In computer science, overhead is any combination of excess or indirect computation time, memory, bandwidth, or other resources that are required to perform a specific task. It is a special case of engineering overhead. Overhead can be a decidin ...

, additional bandwidth used by a communications protocol **

Line code In telecommunication, a line code is a pattern of voltage, current, or photons used to represent digital data transmitted down a communication channel or written to a storage medium. This repertoire of signals is usually called a constrained c ...

or encoding overhead, additional bandwidth required for physical line transmission *

Overhead information Overhead information is digital information transferred across the functional interface between a user and a telecommunications system, or between functional units within a telecommunications system, for the purpose of directing or controlling th ...

, for telecommunication systems * File system overhead, storage or other consideration required by a

file system In computing, file system or filesystem (often abbreviated to fs) is a method and data structure that the operating system uses to control how data is stored and retrieved. Without a file system, data placed in a storage medium would be one larg ...

that is not directly related to data. * Any physical object situated, or action occurring above: **

Overhead line An overhead line or overhead wire is an electrical cable that is used to transmit electrical energy to electric locomotives, trolleybuses or trams. It is known variously as: * Overhead catenary * Overhead contact system (OCS) * Overhead equipmen ...

, for power transmission **

Overhead cable An overhead cable is a cable for the transmission of information, laid on utility poles. Overhead telephone and cable TV lines are common in North America. These poles sometimes carry overhead power lines for the supply of electric power. Power ...

, for signal transmission **

Overhead projector An overhead projector (often abbreviated to OHP), like a film or slide projector, uses light to project an enlarged image on a screen, allowing the view of a small document or picture to be shared with a large audience. In the overhead project ...

, a display system *

Overhead cam An overhead camshaft (OHC) engine is a piston engine where the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustion cha ...

, a mechanical device *

Overhead join An overhead join is a conventional method for an aircraft to approach and safely land at an airfield. It helps a pilot to integrate with any air traffic pattern near an airfield, join any circuit, and land. Aircraft may arrive at the landing site ...

, in air traffic control

See also