During the regular hours of 9:30 a.m. ET to 4 p.m. ET, trading in equities may be paused market-wide if declines in the S&P 500 trigger a "circuit breaker." These occur when the benchmark index falls ...

Even if you aren’t an electronics person, you probably have a working knowledge of circuit breakers. When the lights go out, you find the circuit breaker and flip it back to the on position.

South Korea's Kospi 200 index futures trading was also briefly suspended after falling close to 7% on Monday, while the index ( KOSPI) was down nearly 6%. In Taiwan, circuit breakers were triggered ...