Compound interest explained with real numbers
The maths is one line. What surprises people is how long nothing appears to happen, and how much the compounding frequency matters.
Insights
Document work,
explained properly.
Practical writing about PDF, image and document work — what is actually inside the file, which settings change the outcome, and how to get it right the first time. Every guide is written here, not reprinted.
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Why your PDF will not print properly
Wrong size, missing colour, blank pages, cut-off edges. Almost every PDF printing fault is one of six causes, and five are in the file.
How to send a large file that actually arrives
Every service has a different ceiling and email has the lowest. Which route to use at which size, and why zipping usually does nothing.
How to reorder, insert and remove PDF pages
Page management is three operations that most tools bury under one button. Which to reach for, and how to avoid renumbering yourself into a mess.
HEX vs RGB vs HSL: which notation to use when
Three ways to write the same colour. One is compact, one is programmable, and one is the only one you can reason about in your head.
WCAG contrast requirements, explained properly
Which ratio applies to which element, why grey placeholder text usually fails, and the rules most checkers never mention.
The regex you actually need, and the parts you can skip
A dozen constructs handle almost everything people reach for regex to do. Here they are, plus the two habits that cause most of the bugs.
What makes a good URL slug
Short, lowercase, hyphenated and stable. The rules are simple; the one that actually costs traffic is changing a slug after it is indexed.
How to write a title tag that actually fits
Google truncates on pixel width, not character count, and rewrites about six titles in ten anyway. Here is how to write one that survives both.
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