Happy Buddha is always represented as very stout, with the breast and upper abdomen exposed to view. His face has a laughing expression, and he is also known as the Laughing Buddha. Happy Buddha usually stands in the first hall of the Buddhist monastery.
Happy Buddha is the incarnate image of Maitreya Buddha in Sanskrit term "the Merciful One" which is rendered into Chinese as mi-le. This name is said by some to be derived from the a King, Syriac Molekh.
Maitreya is a Bodhisattva, the principal one, indeed, of Sakyamuni's retinue,
but is not counted among the ordinary disciples. It was in the Tushita heaven
that Sakyamuni met him and appointed him as the successor, to appear as Buddha after the lapse of 5,000 years. Maitreya is therefore the expected Messiah of Buddhists, residing at present in Tushita. Therefore, as opposed to the Past Buddha (Bhaisajyaguru Buddha, or Medicine Buddha) and Present Buddha (Sakyamuni Buddha), Maitreya is the Coming Buddha.