| # | Mark line as comment |
| [C] | Chain a rule with the next rule. |
| [E=var:val] | Assigns to the Environment variable 'var' the value 'val'. |
| [F] | Forbidden - The server returns a 403 error to the client |
| [G] | Gone - Marks pages that no longer exist on the site. |
| [L] | Last rule - |
| [N] | Next - Forces Apache to redo the rewrite process, except using the currently rewritten URL instead of the initial URL |
| [NC] | No Case - case insensitive. |
| [NE] | No Escape - Instruction to parse all output ignoring escaping characters, meaning spaces in the URL will not be replaced with %20 for example. |
| [NS] | No Subrequest - Instruction to skip if it is an internal sub request. |
| [OR] | ‘OR‘ statement. |
| [P] | Proxy - Instructs server to use mod_proxy to handle requests. |
| [PT] | Pass Through - mod_rewrite to send a formatted URL back to Apache. |
| [QSA] | Append query string at the end of the requested URI. |
| [QSD] | Discard query string at the end of the requested URI. |
| [R] | Redirect - 301 permanent redirect (page has moved); 302 temporary redirect. |
| [S=x] | Skip 'x' number of rules if a match is found. |
| [T=MIME-type] | Mime type of the target file. |
