The UK Hydrographic Office offers two levels of service with their chart data; namely, Skipper and Navigator.

The Skipper service, involves a one-off purchase of a chart or set of charts. Ideal, and more cost effective for customers that require a smaller area of chart coverage or that require less regular updates through the quarterly or annual update Skipper service.

The Navigator service is beneficial if worldwide or sizeable chart coverage is required or if up to date data is necessary. Navigator is licenced to the User by an annual charge and provides the User with weekly update CDs allowing their chart set to be kept up to date.

In either case, when a user purchases a chart or set of charts they are supplied with the relevant 'RC' CDs, an Update CD and a licence and permit file. New charts may be added to an existing licence at any time.

For more information on the UK Hydrographic Office visit their website on www.hydro.gov.uk