AI MILESTONES
ten tasks, the year of each, the system, the figure — and the human it was measured against
THE ASCII TABLE
all 128 positions: the column is the three high bits, the row is the four low ones
AUDIO FORMATS
who published each standard, when, what it does to the sound, and how many bits per second it allows
THE BASE32 ENCODING
forty bits to a quantum: five bytes, eight characters and five padding cases
THE BASE64 ENCODING
three bytes become four characters: the alphabet, the tail, and what the "=" at the end is for
BIG-O NOTATION
the seven growth classes: how many steps, how long they take and how far each one lets you go
BINARY COUNTING
five doubling cards build every number from 0 to 31 — exactly the way every computer counts
THE CRON EXPRESSION
the five schedule fields: what each one means, what values it takes, and how to read stars, lists and steps
CSS GRID
the container properties and the item properties per the css-grid-2 specification — and what each does to the layout
BITS, BYTES, KILOBYTES
two scales · 1000 and 1024 · why a drive looks smaller
THE DMX512 PROTOCOL
512 channels down one serial wire, and why a full universe cannot refresh faster than 44 times a second
EAN-13
how thirteen digits become 95 modules of bars and spaces
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
FILE DESCRIPTORS
Three levels between a number and a file: what two numbers of one description share, what two descriptions do not — and where the offset lives
FILE LOCKS
A lock lies on a range of bytes, it has two different kinds of owner, and it guards no byte at all
FILE PERMISSIONS
Nine bits in three triads, three special bits — and why r and x on a directory are different powers
CSS FLEXBOX
main axis and cross axis · which property belongs to which
A NUMBER IN 32 BITS
sign, exponent and significand: what actually sits in a float and what does not
FLOWCHART SYMBOLS
10 shapes, and one algorithm drawn with them
GIT WORKING AREAS
four areas · the command that moves code between them
FILENAME EXPANSION: *, ?, […]
A leading dot and a slash disappear only in filename expansion: the same pattern “*” is seen by case, but not by expansion itself
GO vs RUST
seven questions, the same to both, and the document each answer is written in
HERE-DOCUMENTS
The body reaches the command as a single word, and one quote in the delimiter decides whether it arrives as typed
HTTP METHODS · 2026
ten methods per RFC 9110, 5789 and 10008: which are safe, which are idempotent, which can be retried