This class can be used to recognize and handle Web robots by IP address or user agent. It can check the IP address of the computer or the user agent of the browser program currently accessing the Web server to determine if it is within a range of IP addresses known to be of Web robots like search engine site crawlers or even malicious crawlers. The class can call different callback functions depending on the type of crawler that was identified. It can also be set on debug mode by taking a given IP address or string as user agent instead of the user agent string sent by the accessing browser. The Web robots information is stored in a database. The class can load that database from a text data file. The database can be accessed using supplied database class or a database adapter class from the Zend Framework.