Forum Moderators: phranque
File extensions don't matter. What does matter is that you don't want long dynamic URLs with complex query strings (A query string is not part of a URL, it is data to be passed to the resource *at* that URL).
So avoid things like:
example.com/index.php?action=shop&products=widgets&size=small&color=red&texture=fuzzy
example.com/index.php?action=shop&products=widgets&size=small&color=blue&texture=fuzzy
You'd do better to use:
example.com/shop/small-fuzzy-red-widgets
example.com/shop/small-fuzzy-blue-widgets
In the first case (query-based) you have one page (URL), index.php, with two query strings. In the second case, you have what appears to be two separate pages, so they will do better. No file extension is needed.
If you really want to change .php URLs to .html URLs:
1) Change your scripts and pages to output links as ".html" so that you see them as .html links in your browser.
2) Then use .htaccess to write them back to .php when they are requested from your server, so that your scripts will work properly.
Jim