Guides
Short, practical guides written to answer one question properly. Each links to the tool that does the job.
QR codes
- Putting your menu behind a QR codeThe decisions that stop you reprinting table tents — where the menu lives, static versus dynamic, and the test worth doing first.
- How to create a Wi-Fi QR codeLet guests join your network by scanning instead of typing a 20-character password.
- What size should a QR code be for print?The distance rule, real minimum sizes, and a table you can check before sending artwork to print.
- What is a QR code?What the squares actually mean, why a scratched code still works, and what a QR code can and cannot do.
- Why is my QR code not scanning?Nine causes, ordered by how often they are actually the problem, each with the fix.
For developers
- How to verify a download with a checksumWhat a checksum proves, what it quietly does not, and the commands to run it on macOS, Linux and Windows.
- How to fix common JSON syntax errorsNine causes ordered by how often they actually happen, plus why the reported line number is often not where the mistake is.
- Is MD5 safe?Why MD5 is broken, why that does not make it useless, and what to use for passwords instead.
- UUID v4 vs v7: which should you use?Why v7 indexes so much better than v4, when random is still the right answer, and the creation time v7 hands out for free.
- What is Base64?What those long strings ending in "==" actually are, where they belong, and why they are not a way to hide anything.