MARS
size, distances and time — computed from rotation, orbit and mass
DEVELOPMENTAL MILESTONES · YEAR ONE
2, 4, 6, 9, 12 months per the CDC checklists (2022 revision): 59 milestones that at least 75% of children reach by each age
DEVELOPMENTAL MILESTONES · YEAR TWO
15, 18, 24 months per the CDC checklists (2022 revision): 41 milestones that at least 75% of children reach by each age
SIZE CHARTS
shoes, tops, bottoms — and a centimetre under every grid
STAIN REMOVAL
five stain classes and the method for each — per publication H.E. 2-840 of the University of Kentucky Cooperative Extension
AI MILESTONES
ten tasks, the year of each, the system, the figure — and the human it was measured against
AUDIO FORMATS
who published each standard, when, what it does to the sound, and how many bits per second it allows
THE EXIT STATUS
One byte from a command to the shell: what the standard assigns in it, what it leaves to the system — and why “128 + signal number” is nowhere in the standard
THE FLAGS OF OPEN()
FIVE flags of creating a file — and why O_CREAT|O_EXCL is not a faster check but a check and a creation joined into one indivisible act
${…}: TRIMMING BY PATTERN
The sign says from which end to cut and doubling it says how much: from the same path the same pair of patterns takes away either one character or fifteen
THE ORDER OF REDIRECTIONS
Redirections are done from left to right, and “2>&1” copies where the output points at that very moment: the file first — and it holds two lines; the copy first — one
THE CONDITIONS OF TRAP
FIVE conditions from the standard — EXIT and four signals — and three extensions a conformant shell refuses
ARABICA AND ROBUSTA
two species, six varieties, one difference
MATCHA GRADES
ceremonial, premium, culinary — what is behind the words
SPIRIT HOMELANDS
where the law lets Scotch, bourbon, cognac and tequila be made — seven spirits, three scales of place: a country, a part of one, a drawn zone
SPIRIT RAW MATERIALS
what the law lets whisky, rum, brandy and tequila be distilled from — ten spirits, seven raw materials, two regulations
YELLOW TEA
yellowing under a cover · the step no other tea has
CULINARY KNIFE CUTS
julienne, brunoise, bâtonnet and the family of dice — the Culinary Institute of America dimensions, drawn to true scale
NEAPOLITAN PIZZA DOUGH
four ingredients in the proportions written into an EU regulation
POUND CAKE
four equal weights — a recipe whose name is its ratio
PROTEIN IN FOODS
grams per 100 g · animal and plant · and the state each one was weighed in
ENGLISH PUNCTUATION
twelve marks and the three strokes: a name, a job and one working example for each
LANGUAGE FAMILIES
who is related to whom — on the numerals three and two in twenty-seven languages
THE COLLATZ CONJECTURE
halve the even, triple the odd and add one: the road of 27, the record holders and a problem nobody has solved
THE DOOMSDAY RULE
the weekday of any date in the Gregorian calendar, worked out in the head in three steps
LEAP YEARS
one rule, a cycle of four hundred years and the ninety-seven extra days in it
THE RULE OF 72
the time it takes steady growth to double: the division you can do in your head, how far it misses and why the divisor is what it is
EQUAL TEMPERAMENT
how many cents each interval misses the pure one by, and why exactly that much
TONEWOODS
density, hardness, export · what is measured kept apart from what is taste
THE COMPASS ROSE
the sixteen compass points with exact bearings: four cardinal, four intercardinal, eight in between
USDA HARDINESS ZONES
the 13 zones by average annual extreme minimum — each range in °F and °C, with the a and b half-zones
THE MOMENT MAGNITUDE SCALE
what a single step hides: ×10 in recorded amplitude and roughly ×32 in released energy — drawn to true scale
PLASTIC RESIN CODES
the seven codes on the bottom of an article per ASTM D7611: which resin each number names and what it means for sorting
SPEED THRESHOLDS
six thresholds where a different physics begins · every figure computed, not typed
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
BALLS BY THE RULES
eleven sports at true relative size — circumference, mass, pressure, and who sets them
IMPERIAL UNITS
convert in your head · without a calculator
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
APERTURE, SHUTTER, ISO
one stop is twice the light: three scales with the same step on each
THE TALLEST BUILDINGS
the ten tallest at true scale — and where the floors in them end
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
MOTORCYCLE CLASSES
rake, trail, wheelbase and seat height — six classes drawn at one scale
THE RACING LINE
one corner, three apexes, the time computed
TYRE SIZE
what the sidewall marking is made of and what it works out to