Guides

Deep-dive tutorials and reference material.

The Ultimate CSV Guide
Everything about CSV: format spec, quoting, line endings, tools, and troubleshooting.
The Ultimate JSON Guide
A practical guide to JSON: types, parsing, common errors, and tools.
The Ultimate Regex Guide
Regular expressions for developers — anchors, character classes, groups, and tools.
The Ultimate Guide to Working with Plain Text
Plain text encodings, line endings, case conventions, diffs, and encoding schemes — a practical guide for developers.
Which Legal Documents Your Website Actually Needs
A practical order of operations for the policies, contracts and notices a website, app or business needs, and what each one has to be able to answer.
Geometry Calculators: Which Formula, When
A practical tour of the geometry formulas students and makers actually use — which one applies to the shape in front of you, and how to avoid the input mistakes that produce a wrong answer.
Planning a Term: Timetables, Countdowns and Study Plans
How to turn a syllabus, a book and a pile of deadlines into a plan that survives contact with a school week — and the school-calendar arithmetic that trips most plans up.
Words, Pages and Paper: Getting a Document to Fit
Why a page holds about 275 words and not a fixed number, what a point size change really costs, and the paper and print arithmetic that ruins a print run.
Readability Scores: What the Five Formulas Actually Measure
Why Flesch, Flesch-Kincaid, Gunning Fog, SMOG and ARI disagree by two or three grades, what a syllable heuristic costs, and the structure measures that explain a score.
Typing Speed, Measured Properly: WPM, Accuracy and the Keyboard Underneath
What words per minute really counts, why accuracy predicts speed, how the layouts compare on computed finger travel, and what a browser can and cannot tell you about your keyboard.
Chemistry Calculations, in the Order They Are Meant to Be Done
Moles, molar mass, solution chemistry, balancing and stoichiometry, the gas laws and pH — what each step is for, and the conventions that decide whether the answer is right.
Physics Problems: Find the Unknown, Watch the Units
Kinematics, forces, energy, momentum, circuits and waves — how to tell which relationship applies, what each quantity actually means, and the unit conventions that decide the answer.