Flubber (Flying Rubber) was created in an experiment by Professor Brainard (Ned in the original series, Philip in the remake), at the cost of missing his own wedding day to his fiance (Betsy Carlisle in the original film; Sara Reynolds in the remake). When he learns more about how to use Flubber, he is able to create two variations of it in the form of a cream and liquid, able to give similar bouncing and durability as Flubber to a golf ball, bowling ball, and basketball.
While Flubber is an inanimate substance in the original film, in the remake Flubber is depicted as more of a living gooey creature. He dislikes strong flashes and being bullied, especially around Wilson and his henchmen. His molecular composition allows Brainard to generate a new kind of energy generator. However, neither Brainard or Flubber really knows how it will affect the humans, despite that Wilson swallows him.
During the release of the original film, TIME magazine listed the recipe used for making flubber which is as follows: "To one pound of salt water taffy add one heaping tablespoon polyurethane foam, one cake crumbled yeast. Mix till smooth, allow to rise. Then pour into saucepan over one cup cracked rice with one cup water. Add topping of molasses. Boil till lid lifts and says 'Qurlp'."