Disavow Files: When (and When Not) to Use Them
Most sites should never touch it, says Google itself: the manual-action workflow the tool was built for, and the toxic-score panic it was not.
Nick (ATV Team)
FAQ Schema: Get Expandable Results in Google
Any current FAQ schema tutorial owes you the full story: what Google revoked, what survived the crackdown, and the writing rules the markup amplifies.
Schema Markup: Rich Results Without a Plugin
A machine-readable restatement of facts already on the page: what structured data buys you, stated carefully, and the one-paste implementation.
Fractal Art in Your Browser: Koch, Hilbert, Sierpinski
Replace, repeat, and a triangle grows an infinite coastline: the three classic fractals with their strange numbers, drawn live in twenty-plus browser tools.
GUIDs 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.
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.