1. In this case the Friendly URL is the old, non-Joomla URL (without the domain name). This is the URL users will be entering into the browser. This is a "relative URL", meaning, we just enter the URL without the domain name, that is, "/ref.html".
2. The Internal URL is the URL of the Joomla page we want users to go to when they enter the "friendly URL" in their browser. In this case, we got this URL from the mapped URL that we previously looked at. The internal URL was listed on the list of mappings we saw before. Note: this URL has no leading slash.
3. Click Save.

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