mechanical incendiary device designed to project a long controllable stream of fire

A flamethrower is a device used to shoot fire. They have been used by the military since the days of Greek fire. Most modern military flamethrowers project flaming liquids.

A soldier using a flamethrower in the Vietnam War

Flamethrowers became rare in the 19th century, due to improvements in other weapons. Trench warfare made them more useful again, and the German army began using them in 1915. Flamethrowers were used during World War 2 as a bunker clearing device. Many Axis troops used pillboxes and other small fortifications in Northern France, Germany, and on Pacific Ocean islands. Small fire squads used these weapons to draw them out. Although flamethrowers project flames, burning was not the most common form of death associated with these weapons. Rather, smoke released as a byproduct of combustion presented soldiers with the grim ultimatum between death by smoke inhalation or leaving the trench and facing enemy gunfire.

Due to advancements in ballistic technologies and modern warfare tactics, flamethrowers are much less common in modern theatres. Presently, these weapons have been converted for civilian use for clearing old crops, domestic defense and even landscaping. In 2018, the Boring Company headed by Elon Musk developed a civilian flamethrower in a limited production of 20,000 units. With the prominence of Musk in contemporary culture, these flamethrowers were sold quickly yielding 10 million dollars for the Boring Company in gross revenue.