Circuit symbols help us to plan the circuits before we build them. ... Slide 1 of 2, The circuit symbol for a switch in the 'off' position. Two small circles either side of a gap.

These designations spell out the number of contacts and how they behave during operation. For instance, a basic on/off light switch is an example of a single-pole (i.e., one-circuit) single-throw ...

Here’s what the symbol means and where it came from. The iconic power symbol, explained The power symbol, which can still be seen on nearly all modern PCs and laptops, originated in the 1950s.