A helicopter is a type of aircraft. Helicopters can fly backwards, forwards, and sidewards; it can hover in one place and land in the smallest places. Helicopters fly, but not in the same way as ordinary aircrafts. Aeroplanes fly because of its fixed wings that provide lift when its driven forward through the air, but the helicopter doesn't have fixed wings to provide its lift; a large propeller-like rotor provides the lift, which is mounted horizontally and turned by the engine. Helicopters are known as rotary-wing aircrafts. The word helicopter comes from two Greek words: helix, which means spiral and pteron, which means wing. Leonardo Da Vinci called it the helixpteron which means spiral wing, and that's how we got the word helicopter. The helicopter has many nicknames such as: chopper, eggbeater, whirly bird and also flying windmill. Unlike most airplanes, the helicopters don't need a runway. Helicopters can fly safely at much slower speeds and lower attitudes than other aircrafts. However they cant fly as fast as most planes. Most helicopters cannot exceed 2oo miles per hour. If the helicopter is at faster speeds, strong vibrations develop and this can damage the rotor blades. Helicopters can use more fuel than airplanes, to travel the same distance. In general, Helicopters can fly up to 2-3 hours or less than 600 miles, without refuelling. Helicopters have a big range of sizes, from tiny-single seated models to huge transports that can carry 2 trucks in their cargo hold. Helicopters are very useful especially when there is help needed.