All Tools VerseGUIDs and UUIDs: Unique IDs Explained
128 bits make coordination unnecessary: what the 4 in the third group declares, why a seen collision is always a bug report, and the trade-offs that remain.
Nick (ATV Team)
True Randomness: Coin Flips, Dice and RNG Fairness
Sixty heads in a hundred flips happens to fair coins routinely: what randomness actually looks like, and how to test fairness with arithmetic, not vibes.
Mean, Median, Mode: Read Data Like a Pro
The average is closer to a choice than a fact: 62.14, 40 and 35 all describe the same seven salaries, and the gaps between them are the diagnosis.
Fibonacci and Lucas: Sequences in the Wild
The famous sequence and its lesser-known sibling: the miles-to-km accident, the sunflower spirals that check out, and the nautilus that does not.
Prime Numbers: Tests, Factors and Why They Matter
From testing 97 in four checks to the 600-digit products guarding your browser: the practical prime questions, answered with worked numbers.
Percentages Without Panic: Increase, Decrease, Of
The most used and most fumbled math in adult life, with a short rule for every classic fumble and worked numbers throughout.
Hex to RGB: Color Codes Explained
Six characters, one exact color: the anatomy of a hex code, gray when the pairs match, 16.7 million combinations, and the contrast check that should follow.
Roman Numerals: Convert and Avoid the Classic Traps
Learnable completely in ten minutes: additive reading in blocks, the two traps behind nearly every wrong answer, and where the numerals still live today.
IP Addresses in Binary and Hex (Subnetting Basics)
Subnetting is binary reading with network vocabulary: the AND test routers run billions of times a second, and why masks that look odd in decimal are clean in bits.
Braille on the Web: How the Translator Works
A writing system sized to a fingertip, carried inside Unicode: how the cell works, what instant translation honestly covers, and where transcribers take over.
Unicode vs UTF-8 vs UTF-16: Text Encoding Untangled
One sentence untangles it: Unicode assigns numbers, the UTFs write bytes. With real byte values, the emoji that breaks length checks, and the mojibake cure.
Gray Code: One Bit at a Time (and Why It Matters)
A volume knob between 7 and 8 can briefly read 15: the representation problem, the reordering that fixes it, and the one-line trick that converts.