Fulfils a central role in mathematics as the additive identity of the integers, real numbers, and many other algebraic structures.
- ~3000BC Babylonians begin to use a sexagesimal number system - this is a place-value system without a zero place value.
- 876BC A symbol to represent zero was first used in India.
- ~700 Mathematicians in the Mayan civilization introduce a symbol for zero into their number system.
- 950 Gerbert of Aurillac (later Pope Sylvester II) reintroduces the abacus into Europe. He uses Indian/Arabic numerals without having a zero.
- 1149 Al-Samawal writes al-Bahir fi'l-jabr - he develops algebra with polynomials using negative powers and zero.
- ~1200 Chinese start to use a symbol for zero.