Zero
Zero is the integer between −1 and 1 that represents no quantity. In positional numeral systems, it also marks an empty place value.
Natural number: A number used for counting or ordering; conventions differ on whether it includes zero. Whether zero belongs to the counting numbers depends on how this broader set is defined.
Positional numeral system: A numeral system in which a digit's position determines its contribution to a number. Zero functions as a placeholder within this broader class of numeral systems.
Babylonian numerals: A cuneiform numeral system used in ancient Mesopotamia, primarily based on 60. Babylonian scribes developed a placeholder sign for empty positions, though not a fully independent zero.
Absolute zero: The lowest possible thermodynamic temperature, defined as 0 kelvins. This physical temperature uses zero as a boundary on the absolute temperature scale.
One: The natural number following zero and the multiplicative identity. One represents a single unit, while zero represents none and is the additive identity.
Integer: A whole number, positive, negative, or zero. Zero is the central integer separating positive from negative values.
Decimal numeral system: The base-ten positional numeral system, using the digits 0 through 9. In decimal notation, zero distinguishes values such as 5, 50, and 500.
Maya numerals: A base-twenty numeral system used by the Maya, with a symbol for zero. Maya mathematics independently used zero in positional notation and calendar records.
Zero point energy: The lowest energy a quantum system can possess, even at absolute zero. Quantum mechanics shows that a system's energy need not vanish when temperature reaches zero.
Infinity: An unbounded quantity or mathematical object, treated differently across mathematical contexts. Zero and infinity mark contrasting extremes, but neither is an ordinary finite magnitude in every setting.