billions

Billions is the plural form of billion, a large numerical value used to express very large quantities. In modern standard usage, a billion equals 1,000,000,000 (10^9) in the short scale, which is the prevailing system in the United States, Canada, and most of the world for everyday arithmetic, science, and finance. In the long scale, historically used in parts of Europe, a billion was 1,000,000,000,000 (10^12). To avoid ambiguity, some languages still distinguish 10^9 with the term milliard.

Etymology and scales: The term billion originates from historical naming practices in the long and short scales. The divergence between the scales created differences in what the word signified, leading to ongoing calls for clarification in multilingual or historical texts. In modern international usage, the short scale predominates, and the equivalent 10^9 is almost always understood as a billion.

Usage and context: Billions are used to describe quantities in economics, demographics, and science, such as national expenditures, population counts, and large data measures. Because of regional variation in naming, context matters when reading older or multilingual material. In computations and data storage, decimal billions (10^9) are common, while binary terms used in computing (such as powers of two) employ different prefixes (for example, gibibyte for 2^30) to avoid confusion with decimal billions.

See also: Brief notes on the difference between short scale and long scale, and on milliard as an alternative term for 10^9 in some languages.