In one of my pet projects, I redirect all requests to index.php, which then decides what to do with it:
This snippet in your .htaccess will ensure that all requests for files and folders that does not exists will be redirected to index.php:
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule . index.php [L]
This enables the rewrite engine:
RewriteEngine on
This checks for existing folders (-d) and files (-f):
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
And this does the actual redirecting:
RewriteRule . index.php [L]
You can extend this to pass the requested path to the index.php file by modifying the RewriteRule to the following:
RewriteRule ^(.*)$ index.php?q=$1 [L,QSA]
The ^(.*)$ part tells the rewrite module that we want to pass down the whole requested path as one parameter. The QSA part tells the module to append any query strings to the request. The ?q=$1 tells the module how to pass down the parameter. In this case, it's passed down as the q parameter. You can extend this even further by using regular expressions. For example:
RewriteRule ^([^/]*)(.*)$ index.php?first=$1&second=$2 [L,QSA]
This will pass down the first part of the path as the first parameter, and the rest as the second. So the following request
http://yourhost.com/some/path/somewhere
will result in
http://yourhost.com/index.php?first=some&second=path/somewhere
This allows for some creative ways to do clean URLs.
If it's not working, make sure that mod_rewrite is installed on Apache. On a unix system you can just do
sudo a2enmod rewrite
to achieve that.