0 (zero) is a number representing an empty quantity. In place-value notation such as the Hindu–Arabic numeral system, 0 also serves as a placeholder numerical digit, which works by multiplying digits to the left of 0 by the radix, usually by 10. As a number, 0 fulfills a central role in mathematics as the additive identity of the integers, real numbers, and other algebraic structures. Common names for the number 0 in English are zero, nought, naught (), nil. In contexts where at least one adjacent digit distinguishes it from the letter O, the number is sometimes pronounced as oh or o (). Informal or slang terms for 0 include zilch and zip. Historically, ought, aught (), and cipher, have also been used. Etymology The word zero came into the English language via French from the Italian , a contraction of the Venetian form of Italian via ṣafira or ṣifr. In pre-Islamic time the word (Arabic ) had the meaning "empty". evolved to mean zero when it was used to translate () from India. The first known English use of zero was in 1598. The Italian mathematician Fibonacci (c. 1170–1250), who grew up in North Africa and is credited with introducing the decimal system to Europe, used the term zephyrum. This became in Italian, and was then contracted to in Venetian. The Italian word was already in existence (meaning "west wind" from Latin and Greek ) and may have influenced the spelling when transcribing Arabic . Modern usage Depending on the context, there may be different words used for the number zero, or the concept of zero. For the simple notion of lacking, the words "nothing" and "none" are often used. Sometimes, the word "nought" or "naught" is used. It is often called "oh" in the context of reading out a string of digits, such as telephone numbers, street addresses, credit card numbers, military time, or years (e.g. the area code 201 would be pronounced "two oh one"; a year such as 1907 is often pronounced "nineteen oh seven"). The presence of other digits, indicating that the string contains only numbers, avoids confusion with the letter O. For this reason, systems that include strings with both letters and numbers (e.g. Canadian postal codes) may exclude the use of the letter O. Slang words for zero include "zip", "zilch", "nada", and "scratch". "Nil" is used for many sports in British English.