IBAN check digits catch every wrong digit and nearly every letter typo
An IBAN's check digits caught every wrong digit we typed into SWIFT's 89 example IBANs, and missed a few errors that swa...
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A Korean learner's dictionary needs only 1,465 of Hangul's syllables
Unicode encodes 11,172 Hangul syllables by one formula, and South Korea's 1987 character standard kept 2,350 of them. Ho...
The same Shift_JIS bytes read as 髙 or 騠, depending on the table
Browsers and Microsoft's CP932 table read Shift_JIS the same way, but other converters do not. We decoded all 7,724 two-...
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Neither Chinese punctuation standard requires full-width marks
Mainland China's punctuation standard and Taiwan's handbook measure marks in character cells and never require full-widt...
The most common Chinese typos are homophones
Most Chinese typos are the right sound and the wrong character, picked from a pinyin keyboard's row of candidates. Some...
What CSS ease and ease-in-out actually do
The default CSS easing, ease, is 80% of the way there at half the time, and it does not start from rest. We evaluated th...
What a seal script converter can and cannot do
Seal script got its own Unicode block on 16 September 2026 — 11,328 characters — and a converter will still leave 的, th...
Converting one passage between mainland, Taiwan and Hong Kong punctuation
Taiwan centres its full stops and the mainland puts them bottom left, yet it is the same character. Here is one passage...
Why common Cantonese characters like 嘅 and 咗 could not be typed in Big5
Eleven of the most-used written Cantonese characters, including 嘅, 咗 and 喺, could not be typed in Big5, the tradition...
Why a Chinese character that works in GBK can break in Big5
GB2312, GBK and Big5 write the same Chinese character with different bytes, and none of them can write every character....
Stripping the dots from an email address can merge two different people
Only Gmail's consumer domain and Proton document dots as ignorable. On Google Workspace dots change the address, so two...
The payment QR on the counter is a line of text you can read
ASEAN merchant payment codes all use one published format: a flat string of tag, length and value. Decoding a real paylo...
No ASEAN country has opened the whole 6 GHz band, and China opened none of it
Six ASEAN countries released the bottom 500 MHz of the 6 GHz band and stopped; the United States released all 1,200. Onl...
127.0.0.1 is one of sixteen million loopback addresses
IPv4 reserved the whole of 127.0.0.0/8 for loopback, and the RFC that did it never names 127.0.0.1. Whether the other 16...
WCAG asks for 24 pixels, not the 44 everyone quotes
The 44-pixel tap target is quoted everywhere as the accessibility requirement. It is WCAG's Level AAA figure. The criter...
Z and +00:00 stopped being the same thing in 2024
RFC 9557 moved Z across to mean the instant is known and the local offset is not, while +00:00 kept its older meaning. T...
Valid JSON is not one thing, and three runtimes prove it
A fourteen-byte document containing a lone surrogate escape parses in Node, parses in Python and is refused by PHP — all...
Four ASEAN countries have no time zone of their own
Asia/Phnom_Penh, Asia/Vientiane, Asia/Kuala_Lumpur and Asia/Brunei are not time zones. They are links, and the files beh...
How to Self-Host Gitea or Forgejo with Docker
The environment variable that closes public registration was renamed, so copying an older tutorial leaves your git host...
Why fancy text breaks search and screen readers
The bold and script letters people put in bios are not a font. They are mathematical notation, and the standard that def...
How to Self-Host Paperless-ngx with Docker
Three of its requirements are about the host rather than the application. The user IDs have to match or nothing gets con...
How to Self-Host Uptime Kuma with Docker
Two things break this after it is working. Its data directory cannot live on NFS, and behind a reverse proxy without Web...
What Your Monitoring Costs the Database
Metadata queries are expensive because the server assembles the answer by walking itself. Measured on production with th...
How to Find What Is Scanning Your Tables
Knowing a table is scanned tells you little; knowing which statement scans it tells you everything. Reading MySQL's stat...
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