A momentary switch is a type of switch that only remains in its on state as long as it is being actuated (pressed, held, magnetized, etc.).
Momentary switches come in a variety of different forms, including:
- Push buttons
- Rocker switches
- Slide switches
- Toggle switches
- Reed switches
The number of poles refers to the number of circuits that the switch controls, while the number of throws refers to the number of positions that the switch can have. For example, a single pole single throw (SPST) momentary switch has two terminals and can be either on or off.