Anonymous FTP is a setting which allows users to login to your FTP server anonymously by not requiring any login credentials.
This feature may be useful to clients wanting to grant access to a set of files to a large number of people, however this can pose a severe security threat and it is strongly encouraged to leave this feature disabled.
Anonymous FTP can only be enabled on accounts that have a dedicated IP address, these can be added to you hosting account via the Raid Host account addon area or by contacting Raid Host Support.