Originally Posted by GrouchyAdmin

A quick note: Using .htaccess instead of server rules causes extra file, and rule lookups for each request, which will eventually cause a slowdown, and it won't work if AuthConfig is not set to Override. (The former is incredibly common with virtualhosts; it makes the admin's job easier.)

It's a quick way to make changes if you do not have access to your webserver's configuration, but if you do, there are better ways to set it up, such as in the webserver config file for that host.

Always wrap your statements properly.

Putting: RewriteEngine On in your .htacess is not as safe as:

<IfModule mod_rewrite.c>
RewriteEngine On
</IfModule>

In case if someone screws up on a webserver upgrade, the above will say 'Ok, so, rewrite isn't here, but we can deal with that.' The former will cause a 500 error, and your site will be down until someone notifies the administration that something bad happened.

...end of hijack.