A Piece of Eight is a Spanish silver coin that was widely used in the 16th to 19th centuries. It was also known as a REAL, reals, piaster, PESO, and octo. The term 'REAL' is derived from the Spanish word for 'ROYAL, ' and it was originally worth 8 reales. The piaster was a Turkish coin, and the PESO was a Mexican coin. The octo was a French coin. All of these coins were worth 8 reales, hence the name Piece of Eight.