1. A method of providing rating information in respect of Uniform Resource Identifiers to a client terminal, the method comprising: 1) identifying a Uniform Resource Identifier at the client terminal; 2) sending a first query to a rating server over an IP network, the query including as a query string a first component of the identified Uniform Resource Identifier or a derivative of that first component; 3) receiving the first query at the rating server and determining whether or not a rating exists for the query string; 4) sending a response including a determined rating, or an indication that no rating exists, to the client terminal; 5) receiving the response at the client terminal and, if a rating included in the response so indicates or if the response otherwise so indicates, then sending a further query to the rating server, the further query including as a query string said first component and a second component of the identified Uniform Resource Identifier, or a derivative of the first and second components; 6) repeating steps 3) to 5) one or more times as required, adding for each iteration a further component to the query string.