From the notebook
33 in-depth articles on the questions the tools raise — the reasoning shown rather than summarised, with the relevant tool linked at the end of each one.
Passphrase or password: which should you actually use?
Real words in a row versus random characters — how the two compare on strength, memory and everyday usability.
Lossy vs lossless compression: what you're actually trading
The one decision behind every image file size — what gets thrown away, what stays, and when it matters.
HEX, RGB and HSL: three ways to say the same colour
What each notation means, how to read one at a glance, and when to reach for each.
JSON for beginners: the format that runs the web
Objects, arrays, and the five syntax rules that trip everyone up exactly once.
What a hash function actually does (and what it doesn't)
One-way fingerprints for data: how hashing works, what it's for, and why it's not encryption.
Password entropy, explained without the maths degree
What "128 bits of entropy" actually means, why length beats cleverness, and the one assumption every strength meter quietly makes.
Regular expressions: the 20% you'll use 80% of the time
The handful of regex patterns that cover most real jobs, explained without the theory.
Resize first, compress second: the order that saves quality
Why the sequence of operations changes the result, and the simple workflow that gets it right.
JPEG, PNG or WebP? Picking a format without overthinking it
Three formats cover nearly every job on the web. Here's a simple decision rule for each, plus the two traps that catch people out.
Colour harmonies: the rules behind palettes that work
Complementary, analogous, triadic — what the classic harmony rules are and why they please the eye.
UUID versions, explained: which one do you want?
The common UUID versions, what the version digit means, and when random v4 is the right call.
CSV: the simple format with surprisingly strict rules
Commas, quotes and newlines — the quoting rules that make CSV work, and what breaks them.
WebP: the format that does both jobs
Smaller than JPEG, sharper than PNG — what WebP is, where it works, and when to still avoid it.
Where lorem ipsum actually comes from
Cicero, a 16th-century printer and 2,000 years of placeholder text — the real story.
What the WCAG contrast ratio actually tells you
A contrast ratio is computed arithmetic, not a vision test. What the number means, where the 4.5:1 line comes from, and what it can't tell you.
CSS gradients: from flat colour to depth in one line
Linear, radial, stops and angles — building gradients by hand instead of guessing.
Base64 is not encryption: what it is and isn't
The encoding everyone mistakes for security — what Base64 actually does and when to use it.
Why reusing passwords is the fastest way to get hacked
Credential stuffing in plain words: how one breached site becomes every site, and the habit that stops it.
Title case: the capitalisation rules nobody taught you
Which words get capitalised in a heading, and why style guides disagree with each other.
Favicon sizes in 2026: what you actually need
From 16-pixel tabs to 192-pixel home screens — the complete set, and why browsers are so picky.
Building colour palettes everyone can read
Contrast, lightness steps and colour-blindness checks for palettes that survive the real world.
URL encoding: why your links have all those %20s
Percent-encoding in plain words: which characters change, where, and the query-vs-path trap.
Two-factor authentication, without the jargon
What 2FA adds on top of a password, the common methods ranked, and where its protection ends.
Why your word count never matches Word's
Hyphens, em dashes and numbers: the quiet disagreements between every counter ever made.
Transparency, explained: alpha channels without the headache
Which formats keep transparency, which silently drop it, and how to avoid the white-box surprise.
Colour for dark mode: it's not just inverted
Why colours behave differently on dark backgrounds, and how to adapt a palette properly.
Minified vs beautified code: what's the difference?
Why production code looks like alphabet soup, and when readability wins over bytes.
Where random numbers come from (and why Math.random isn't enough)
Pseudorandom vs cryptographically secure randomness, and what your browser does differently.
How to read a diff like a developer
Plus, minus and context lines — the anatomy of a diff and what each part is telling you.
SVG on the web: when vectors beat pixels
Infinitely scalable, tiny file sizes — and three situations where SVG is the wrong choice.
OKLCH: the colour space designers are switching to
A perceptually uniform way to describe colour — what it fixes about HSL, in plain words.
UTF-8: how text became universal
Bytes, code points and emoji — the encoding that ended the era of garbled text.
The quiet power of plain text
No formatting, no lock-in, readable forever — why the humblest format keeps winning.