A coal bin is a container used for storing coal. There are various synonyms for this word, including coal bunker, coal house, coal shed, coal cellar, and coal store. Coal bunkers are typically located outside a building, while coal houses are usually attached to or integrated into a building. Coal sheds may resemble small buildings, while coal cellars are often located underground. A coal store may be a room in a larger building designated for the storage of coal. Regardless of the name, these containers were commonly used in the past to store coal for household heating purposes.