What is the origin of the idiom "in two shakes" and when to use it?

The exact origin of the idiom "in two shakes" is uncertain, but it is believed to have originated in the mid-19th century. The phrase likely developed from the expression "a shake," which referred to a short period of time or a brief moment. The addition of "two" in the phrase "in two shakes" emphasizes an even shorter duration, further emphasizing the quickness or immediacy of an action. It is often used in informal conversations or casual writing to convey a sense of immediacy.