Ben Kolo, owner of Mr. Electric of Central Iowa reveals their purpose, ‘Single-pole switches control one light ... control of a light from two locations.’ A double toggle switch like this ...

toggle switch single pole double throw (SPDT) switch connects one input to one of two outputs allows switching between two circuits, unlike SPST version which only connects/disconnects one circuit ...

Push to make switch (PTM) is a momentary switch that closes the circuit only while pressed and is commonly used in doorbells and keyboards. Single pole, single throw switch (SPST) is a latching ...