(1) A network cross connect. See
Ethernet switch.
(2) In programming, a bit or byte used to keep track of some event. The term is sometimes synonymous with the branch command.
(3) In programming, a statement that saves the programmer from having to write multiple compare statements. See
event loop.
(4) A modifier of a command. For example, in the Windows/DOS command
dir /p the
/p is a switch that modifies the Dir command to pause after each screenful. See
Dir.
(5) A mechanism that allows each key to be depressed on a keyboard. See
mechanical keyboard.
(6) A mechanical or electronic device that directs the flow of electrical or optical signals from one side to the other. Switches with more than two ports, such as a LAN switch or PBX, are able to route traffic.
Not Entirely Intuitive
When a switch is closed, current flows and the light or motor is now "on." When opened, current stops, and the light or motor is off. Although "open" might seem to mean "turn something on," opening a switch turns it off, and vice versa. See
transistor,
Ethernet switch,
softswitch,
PBX and
data switch.
Mechanical and Semiconductor Switches
The semiconductor transistor performs the same function as a light switch on the wall. The switch is electronically closed by sending a pulse to the trigger. See
transistor.
A Manual Switch
This early switch panel from New York Electric Switchboard Company was used to manually open and close electric lines.