Enhetprefixets

Enhetprefixets refers to the system of prefixes placed before unit names to indicate multiples or submultiples of a unit. The term is commonly used to describe the family of prefixes employed in many measurement systems, most notably the prefixes defined for the International System of Units (SI).

SI prefixes denote powers of ten, including kilo- (10^3), centi- (10^-2), milli- (10^-3), micro- (10^-6), nano- (10^-9), as well as mega-, giga-, tera-, peta-, and smaller prefixes such as femto- and atto-. Other prefix systems, such as binary prefixes (kibi-, mebi-, gibi-), are used in specific contexts but are not part of the SI.

Usage rules: Prefixes are typically attached directly to the unit symbol without a space and are written in lowercase (for example, km, mg, ms). The combination yields compound units that express large or small magnitudes. Some unit names have conventional spellings or capitalization that affect readability in different languages.

History and standardization: Unit prefixes were developed to provide a consistent scale for measurements. SI prefixes were standardized through international metrology bodies, including the CGPM, CIPM, and BIPM. The modern set of decimal prefixes has been in place since the 1960 revision of the SI, with occasional updates based on consensus.

Enhetprefixets underpins scientific, industrial, and educational usage by enabling concise and precise representation of quantities across many domains.