Piggy bank (sometimes penny bank or money box) is the traditional name of a coin accumulation and storage receptacle; it is most often, but not exclusively, used by children. The piggy bank is known to collectors as a "still bank" as opposed to the "mechanical banks" popular in the early 20th century. These items are also often used by corporations for promotional purposes.
Piggy banks are typically made of ceramic or porcelain, and serve as a pedagogical device to teach the rudiments of thrift and savings to children; money can be easily inserted, but in the traditional type of bank the pig must be broken open for it to be retrieved. Most modern piggy banks, however, have a rubber plug located on the underside; others are made of vinyl and have a removable nose for easy coin access. Some piggy banks incorporate electronic systems which calculate the amount of money deposited.
In Middle English, "pygg" referred to a type of clay used for making various household objects such as jars. People often saved money in kitchen pots and jars made of pygg, called "pygg jars". By the 18th century, the spelling of "pygg" had changed and the term "pygg jar" had evolved to "pig bank."
Once the meaning had transferred from the substance to the shape, piggy banks began to be made from other substances, including glass, plaster, and plastic. The general use of piggy banks is to store loose change in a quaint, decorative manner. Modern piggy banks are not limited to the likeness of pigs, and may come in a range of animal shapes, sizes and colors. Many banks today depict popular children’s television, movie, and book characters. Many people collect coin banks as a hobby.