Glossary & Sources

Length ↗

• BIPM SI Brochure, 9th ed. metre defined as distance light travels in 1/299,792,458 s
• NIST SP 811 inch = 25.4 mm exactly; imperial-to-metric conversion factors
• Wikipedia: Metre

Weight & Mass ↗

• BIPM SI Brochure, 9th ed. kilogram redefinition via Planck constant h (2019)
• NIST SP 811 pound and other customary mass units
• Wikipedia: Kilogram

Temperature ↗

• BIPM SI Brochure, 9th ed. kelvin defined via Boltzmann constant; thermodynamic temperature
• Wikipedia: Celsius
• Wikipedia: Fahrenheit
• Wikipedia: Kelvin

Volume ↗

• BIPM SI Brochure, 9th ed. litre = 10⁻³ m³
• NIST Handbook 133 US customary volume units: fluid ounce, cup, quart, gallon
• Wikipedia: US Customary Units US vs. imperial gallon differences

Area ↗

• NIST SP 811 square metre and SI derived area units
• Wikipedia: Hectare
• Wikipedia: Acre

Time ↗

• BIPM SI Brochure, 9th ed. second defined via caesium-133 hyperfine transition frequency
• IERS: Coordinated Universal Time UTC definition and leap seconds
• Wikipedia: Second

Speed ↗

• BIPM SI Brochure, 9th ed. metre per second as SI derived unit of speed
• NIST SP 811
• Wikipedia: Knot 1 nautical mile per hour; used in aviation and maritime

Cooking ↗

• NIST Handbook 133 US customary cooking measures: teaspoon, tablespoon, cup
• Wikipedia: Cooking weights and measures US vs. UK tablespoon and cup size differences

Fuel Efficiency ↗

• US EPA: fueleconomy.gov MPG standards and official fuel economy labelling
• Wikipedia: Fuel economy in automobiles L/100 km vs. MPG; inverse relationship

Pressure ↗

• BIPM SI Brochure, 9th ed. pascal = 1 N/m²; SI derived unit
• Wikipedia: Pascal
• Wikipedia: Atmosphere (unit) standard atmosphere = 101,325 Pa exactly

Energy ↗

• BIPM SI Brochure, 9th ed. joule = 1 kg·m²/s²; SI derived unit
• Wikipedia: Calorie thermochemical vs. International Table calorie
• Wikipedia: British thermal unit

Power ↗

• BIPM SI Brochure, 9th ed. watt = 1 J/s; SI derived unit
• Wikipedia: Horsepower mechanical vs. metric hp; James Watt's original definition

Force ↗

• BIPM SI Brochure, 9th ed. newton = 1 kg·m/s²; SI derived unit
• NIST SP 811
• Wikipedia: Pound-force lbf vs. lbm distinction; gravitational vs. mass units

Torque ↗

• BIPM SI Brochure, 9th ed. newton-metre as SI unit of torque
• Wikipedia: Torque τ = F × r; distinction between torque and energy (work)

Angle ↗

• Wikipedia: Radian SI supplementary unit; arc length equals radius at 1 rad
• Wikipedia: Degree (angle) Babylonian 360° system and its divisibility
• Wikipedia: Gradian metric-era surveying unit; 400 grad = full circle
• Wikipedia: Milliradian optics and ballistics: 1 mrad ≈ 1 m at 1 km distance

Frequency ↗

• BIPM SI Brochure, 9th ed. hertz = 1 cycle per second; SI derived unit
• Wikipedia: Hertz
• NIST CODATA: Planck constant h = 6.626 × 10⁻³⁴ J·s; E = hf links frequency to photon energy

Digital Storage ↗

• IEC 80000-13:2008 official standard defining KiB, MiB, GiB, TiB, PiB binary prefixes (1998)
• Wikipedia: Binary prefix SI decimal vs. binary prefix disambiguation; OS display discrepancy

Number Base ↗

• Wikipedia: Numeral system
• Wikipedia: Hexadecimal base-16; each hex digit represents exactly 4 binary bits
• Wikipedia: IEEE 754 64-bit floating-point format; 2⁵³ − 1 safe integer precision limit

Currency ↗

• IMF Data International Monetary Fund exchange rate reference data
• European Central Bank: Euro reference rates
• Wikipedia: Reserve currency US dollar as global reserve currency; Bretton Woods system history

Pace ↗

• World Athletics official road race distance standards; min/km and min/mile pace references
• Wikipedia: Pace (speed) pace as inverse of speed; relationship to time-per-distance metrics
• NIST SP 811 mile = 1,609.344 m exactly; basis for min/mile ↔ min/km conversion

Density ↗

• BIPM SI Brochure, 9th ed. kg/m³ as SI derived unit of density (kilogram per cubic metre)
• NIST SP 811 lb/ft³ and lb/in³ conversion factors
• Wikipedia: Density ρ = m/V; Archimedes' principle; reference densities for common materials

Flow Rate ↗

• BIPM SI Brochure, 9th ed. m³/s as SI derived unit of volumetric flow rate
• NIST SP 811 US gallon = 3.785411784 L; gallon per minute (GPM) conversion
• Wikipedia: Volumetric flow rate

Data Transfer Rate ↗

• IEC 80000-13:2008 SI prefixes for data rates: kilo=10³, mega=10⁶, giga=10⁹ (decimal)
• Wikipedia: Data-rate units bits vs. bytes; ISP Mbps vs. OS MB/s; factor of 8 conversion
• IEEE 802 Ethernet standards 10/100/1000 Mbps and 10/40/100 Gbps Ethernet definitions

Illuminance ↗

• BIPM SI Brochure, 9th ed. lux = 1 lm/m²; SI derived unit of illuminance; candela as SI base unit
• Illuminating Engineering Society (IES) recommended illuminance levels for workplaces, roadways, and interiors
• Wikipedia: Lux 1 foot-candle = 10.7639 lux; typical illuminance values for common environments

Typography Units ↗

• W3C CSS Values and Units Level 4 official CSS unit definitions: px, pt, pc (pica), em, rem, in, cm, mm; 96px = 1in
• Wikipedia: Point (typography) 1 CSS pt = 1/72 in; history of the typographic point from Didot to PostScript
• Wikipedia: Pica (typography) 1 pica = 12 points = 1/6 inch; used in print layout for column and margin widths

Electric Units ↗

• BIPM SI Brochure, 9th ed. ampere as SI base unit; volt and ohm as derived units; V = I × R (Ohm's Law)
• NIST SP 811 SI electrical unit definitions and prefixes (µ, m, k, M)
• Wikipedia: Ohm's Law V = IR; relationship between voltage, current, and resistance