What is a URL slug?
A URL slug is the part of a URL that identifies a specific page in human-readable form. For example, in "https://example.com/how-to-build-a-website", the slug is "how-to-build-a-website". Good slugs are descriptive, lowercase, and use hyphens between words.
Should I use hyphens or underscores in slugs?
Google recommends hyphens (-) over underscores (_) for URL slugs. Google treats hyphens as word separators but treats underscores as word joiners. "free-tools" = two words; "free_tools" = one compound word in search engine interpretation.
What are stop words in slug generation?
Stop words are common words (a, an, the, in, on, at, for, of, etc.) that add little SEO value to URLs. Removing them keeps slugs shorter and more keyword-focused. E.g., "the best tools for the web" → "best-tools-web".