I'm a complete novice when it comes to rewrites, I don't know enough about the code, and am frankly terrified of doing the wrong thing in converting my .html web pages to .php. (BTW, the reason for the conversion - to add header and footer includes plus dynamic features.)
So far, I've found the .htaccess rewrite rule.
RedirectMatch permanent ^(.*)\.html$ $1.php
(I'd prefer not to include rewriting .htm pages as all of MY pages are .html)
However, I'm very concerned about how search engines will treat this, and the implications for getting the site to be re-indexed.
I've read that a better SEO technique may be to set up a 301 redirect (or is this exactly the same as what I've just proposed?)
RedirectMatch 301 (.*)\.html$ http://www.example.com$1.php
I'm concerned that "playing" with htaccess may land me in deep waters, and any advice much appreciated.