Termination

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This article is about the technical term. For use in a workplace setting, see termination of employment. For termination of pregnancies, see abortion

Termination as a technical term has different meanings.

In electronics, it refers to the need to put a terminator (either a resistor or a resistor-capacitor network) on the unconnected end of a transmission line, to prevent signal reflections due to the impedance mismatch between the line and the empty space beyond its end. In computer hardware in particular, electrical terminators are needed in many bus-style communication channels, such as thin-wire Ethernet and SCSI. Some devices that attach to such channels are self-terminating: they are capable of sensing whether a terminator is needed, and configuring themselves accordingly.

In electrical wiring a termination point is where a cable or circuit or other facility ends and can be connected to another.

In computability theory and computer programming, a crucial part of the definition of an algorithm is that it must terminate—that is, produce its answer after running for a finite number of steps. Whether this number is or isn't too large for practical execution of the algorithm on a real computer is the subject of computational complexity theory.

Also in computer programming, termination deals with how a program, process, task, or thread ends its execution, allowing the operating system to reclaim the resources it was using and to pass an exit status to its parent process.

In numerical analysis, most computations involve working with real numbers, which is a feat provably beyond the capabilities of finite-state machines (which is what all practical digital computers are). In essence, the problem is that an algorithm for computing a real number to infinite precision would never terminate. However, practical algorithms can all be shown to converge, thus, they can be made to terminate simply by accepting a limit on the achievable precision of the computation.

In telecommunications, termination refers to the delivery of a call to the recipient. For example, if a customer on BT were to call someone on Vodafone, the call's origination lies with BT and the call's termination lies with Vodafone. BT will charge the customer for making the call; in turn, Vodafone will charge BT for providing the termination service.