What makes a good slug
Lower case, words separated by hyphens, nothing else. Hyphens rather than underscores because search engines treat a hyphen as a word separator and an underscore as a joiner — photo_editing reads as one word, photo-editing as two.
Shorter is better. Dropping the, a and of costs nothing and makes a URL that survives being pasted into an email without wrapping.
Accents and other scripts
Accented letters are transliterated rather than stripped, so café becomes cafe and not caf. German umlauts follow the convention of their own language where it is unambiguous.
Non-Latin scripts are a genuine choice rather than a bug. A Chinese or Arabic title can be percent-encoded and stay meaningful to readers of that language, or transliterated into Latin and stay readable in a link. Neither is wrong; pick one and be consistent across the site.
Frequently asked questions
Hyphens or underscores?
Hyphens. Search engines treat them as word separators and underscores as joiners, so photo_editing reads as a single word.
What happens to accented characters?
They are transliterated, so café becomes cafe rather than caf. Dropping them entirely would mangle the word.
Should I change a slug after publishing?
Only with a redirect in place. Changing it without one breaks every existing link and discards whatever ranking the old URL had.
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