Before there were retroreflective coatings on road signs, some places used retroreflective dots to trace the letters and shapes.
I like this related one too
Nice and not US-specific. However, our railways use it sometimes to highlight black text for some reason.
Edit: Added topic to talk page!
For some reason my lemmy client, Thunder, can’t display that image from Wikipedia, but the URL is correct. I can open it in a browser.
Reuploading it to Lemmy in case others have the same issue.
This may be because the URL contains non-ASCII, which I haven’t percent-encoded, despite having manually changed
(
and)
to%28
and%29
to prevent the parentheses from interfering with Markdown syntax.That could be it. Incidentally, the image displays fine in the web UI. Must be a bug in Thunder.