SEO Friendly URLs with PHP - htaccess redirect - how to set up

SEO Friendly URLs with PHP

http://www.9lessons.info/2011/04/seo-friendly-urls-with-php.html

.htaccess
URL rewriting file. Redirecting original URL 9lessons.info/article.php?url=test.html to 9lessons.info/test.html

RewriteEngine On

RewriteRule ^([a-zA-Z0-9-/]+).html$ article.php?url=$1
RewriteRule ^([a-zA-Z0-9-/]+).html/$ article.php?url=$1