Buffet originated in Sweden in the 16th century. Buffet was originally a pre-dinner gathering for drinks and was not a part of the main course. The buffet is meant to be eaten standing and hence should only consist of dishes which can be eaten by a spoon or fork! The all you can eat buffet is attributed to Herb Macdonald who introduced this idea in 1946, Minneapolis.
According to another legend the concept of serving buffet originated in France in the mid 17th Century when men would unexpectedly visit homes of ladies they would want to woo. This visit would make the kitchen staff serve what ever was available in cold rooms as buffet!