Undecimal (also known as unodecimal, undenary, and the base 11 numeral system) is a positional numeral system that uses eleven as its base. While no known society counts by elevens, two are purported to have done so: the Māori (one of the two Polynesian peoples of New Zealand) and the Pañgwa (a Bantu-speaking people of Tanzania). The idea of counting by elevens remains of interest for its relation to a traditional method of tally-counting practiced in Polynesia.[1][2] During the French Revolution, undecimal was briefly considered as a possible basis for the reformed system of measurement.[3] Undecimal numerals have applications in computer science,[4] technology,[5] and the International Standard Book Number system.[6] They also occasionally feature in works of popular fiction.[7] In undecimal, a capital letter (often A, the symbol for 10 in hexadecimal; T, the first letter of the English word "ten"; or X, the Roman numeral 10) or the digit ↊ (called "dek") is typically used as a transdecimal symbol to represent the number 10.