Dash (Hyphen) or Underscore in URLs: Which one to use and when?

Whether to use dashes or underscores in a URL depends on which part of the URL you are changing as well as your purpose. It's not always a simple answer.

dashes-versus_underscores; The Definitive Guide

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Dash or Underscore in URL for SEO (Finally Answered) ‐ sitecentre®

URL Best Practice: Hyphens, Underscores, or No Separators?

Hyphens vs. Underscores in URLs

c# - Add Razor Page' Dialog does not allow hyphens in a filename - Stack Overflow

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Underscores vs. dashes in URLs

What Is a 3-Em Dash? (and When to Use It and How to Insert It)

Dash or Underscore in URL for SEO (Finally Answered) ‐ sitecentre®

Dash - Wikipedia