Strike action, also called labour strike, on strike, greve (of French: grève), or simply strike, is a work stoppage caused by the mass refusal of employees to work. A strike usually takes place in response to employee grievances. Strikes became important during the Industrial Revolution, when mass labour became important in factories and mines. In most countries, they were quickly made illegal, as factory owners had far more political power than workers. Most western countries partially legalized striking in the late 19th or early 20th centuries.

Strikes are sometimes used to put pressure on governments to change policies. Occasionally, strikes destabilise the rule of a particular political party or ruler. In such cases, strikes are often part of a broader social movement taking the form of a campaign of civil resistance. A notable example is the 1980 Gdańsk Shipyard strike led by Lech Wałęsa. This strike was significant in the long campaign of civil resistance for political change in Poland, and was an important mobilised effort that contributed to the fall of the Iron Curtain and the end of communist party rule in eastern Europe.

Lisa Marie Simpson is a fictional main character in the animated television series The Simpsons. She is the middle child of the Simpson family. Voiced by Yeardley Smith, Lisa first appeared on television in The Tracey Ullman Show short "Good Night" on April 19, 1987. Cartoonist Matt Groening created and designed her while waiting to meet James L. Brooks. Groening had been invited to pitch a series of shorts based on his comic Life in Hell, but instead decided to create a new set of characters. He named the elder Simpson daughter after his younger sister Lisa Groening. After appearing on The Tracey Ullman Show for three years, the Simpson family were moved to their own series on Fox, which debuted on December 17, 1989.

At eight years old, Lisa is the second child of Homer and Marge, younger sister of Bart and older sister of Maggie. She is highly intelligent and plays the baritone saxophone. She has been a vegetarian since season 7, converted to Buddhism in season 13 and advocates for a variety of political causes, including the Tibetan independence movement. She has appeared in other media relating to The Simpsons – including video games, The Simpsons Movie, The Simpsons Ride, commercials and comic books – and inspired a line of merchandise.