Collectibles are items of human manufacture considered worth keeping. People collect all types of things, from valuable antiques to seashells to cereal boxes. There is no hard-and-fast rule about the hobby of collecting.
Collecting should be distinguished from hoarding, usually considered an unhealthy pastime. Hoarders collect items compusively and store them in higgledly-piggledly fashion, oftne just pioling them in their living spaces.
Collectors, on the other hand, ensure that their collections are clean and sanitary; they are stored neatly and often displayed in shelves or cases intended for that purpose. Collectors also organise their articles; details of a small collection may be kept 'in someone's head', but large collections are generally catalogued. Even collections composed of items of apparently no intrinsic value can end up having a monetary value, due to the size, nature, interest or scarcity of the collection: cardboard cereal boxes are an example.