For example: STRING1 Mozilla/4.0 (compatible MSIE 5.0 Windows NT DigExt) STRING2 Mozilla/4.75 [en](X11 U Linux2.2.16-22 i586) ^Win will not find Windows inSTRING1 but ^Moz will find Mozilla. Question Mark: https?://university.intranet.net/mod/page/view.php\?id=180.* A ? means the preceding character is optional. For example: colou?r will find both color (u is found 0 times) and colour (u is found 1 time). Therefore, the s (in https) becomes optional and allows users to come in from http or https. Backslash: ^https?://university.intranet.net/mod/page/view.php\?id=180.* If there is a special character that needs to be read literally, you have to put a backslash before it. For example: The question mark in… http://university.intranet.net/mod/page/view.php?id=180 …is part of the actual URL. Therefore, you must add the backslash before the question mark, so that Tizra understands to look for a question mark in the URL. The asterisk: ^https?://university.intranet.net/mod/page/view.php\?id=180.* The asterisk * matches when the preceding character occurs 0 or more times. For example: tre* will find tree (e is found 2 times) and tread (e is found 1 time) and trough (e is found 0 times). Also see: Adding Additional Site Linking Match Patterns