SPEED THRESHOLDS
six thresholds where a different physics begins · every figure computed, not typed
ANIMALS
the main branches — from comb jellies to chordates · who is actually related to whom
VERTEBRATES
from lamprey to bird · and why "fish" and "reptiles" are not groups
CROCHET SYMBOLS
the standard chart symbols, abbreviations and US/UK name differences — per the Craft Yarn Council standards
MORSE CODE
26 letters and 10 digits · dot, dash
THE BASKETBALL
four FIBA sizes with their circumference and mass — and why the rules set a bounce, not a pressure
CURRENCY MINOR UNITS
178 codes in the standard: 139 currencies divide by 100, 17 do not divide at all, 7 divide by 1,000 — and 25 codes are not money you can spend
SI UNITS WITHOUT NAMES
the endless rest: assembled from the base and the named units, and never with a factor
THE WORLD'S TIME OFFSETS
37 offsets from UTC−11:00 to UTC+14:00 — a spread of 25 hours over a 24-hour day
BICYCLE CLASSES
frame, wheel by ISO 5775 and handlebar — three signs of a class, and what the frame is rated for
CAR CLASSES
segments A to F by length and bodies by box count — how to name any car you see