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. Their shape is most often that of a little pig. Many financial services companies use piggy banks as logos for their savings products. Piggy banks are slowly becoming extinct due to the modernising of young children which encourages them to open a junior savings account, instead of keeping their money safe in a piggy bank, where it is vulnerable to theft.