Ronald McDonald is a clown character used as the primary mascot of the McDonald's fast-food restaurant chain. In television commercials, the clown inhabited a fantasy world called McDonaldland to which he had adventures with his friends Mayor McCheese, the Hamburglar, Grimace, Birdie the Early Bird and The Fry Kids. As of 2003, McDonaldland has been largely phased out, and Ronald is instead shown interacting with normal children in their everyday lives.

In Japan, Ronald McDonald is called Donald McDonald due to a lack of a clear "r" sound in Japanese enunciation. In China, out of respect for Ronald McDonald as an adult, children refer to him as Uncle McDonald. In Thailand, Ronald McDonald greets people in the traditional Thai "wai" greeting gesture of both hands pressed together.

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