The plane part that was discovered on Reunion Island off the coast of Madagascar was determined to be part of Malaysia Airlines Flight MH370, Malaysian officials announced Wednesday.

So what exactly is the piece that was found? Malaysia Airlines referred to the Boeing 777 airplane component as a “flaperon.”

Located on the rear edge of the wing, the flaperon is a segment that helps stabilize the plane, particularly when it’s flying at low speeds (like during takeoff and landing).

It’s a mix of two other components -- a flap and an aileron (another part used to maintain balance) -- and can be controlled by the pilot through a computer.

“A flaperon is part of the flap structure of the aircraft along the trailing edge, but unlike a traditional flap which does not move up or down except when being extended or retracted, a flaperon at certain speeds becomes part of the flight controls and deflects up and down with the ailerons,” said ABC News aviation consultant John Nance.

“As the speed increases and the flaps are retracted the flaperons disappear inside the back of the wing and all the lateral control is achieved,” he said.

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