.htaccess files are tricky
.htaccess files are quite tricky because of how powerful they are. You can disable your entire server with one typo, so its not something to take lightly. Over at Narendra Dhami’s blog he’s written a nice little intro with warning.
Behind the Scenes with Apache’s .htaccess
First, A Word of Warning
Keep in mind that one little typo or incorrect rule within an .htaccess file can cause an internal server error and take your entire website offline. Especially if you’re new to using an .htaccess file, I highly recommend setting up a test directory to work on your .htaccess file. In addition, always make a backup of your .htaccess file before making any changes. That way, if you do happen to make a typo or other error, you can load your backup file again to keep your website up and running while you look for the source of the problem(s).