1. A method of managing metadata comprising: maintaining a database of metadata records, said metadata records each corresponding to one or more media files and containing information relating to content of the corresponding media files, said media files being adapted for rendering by a media player program executed on one or more client computers; generating a unique logical identifier for each of the metadata records, said logical identifiers being configured for use in querying the metadata database; defining a base type corresponding to each of the logical identifiers, said base types being representative of the information contained in the respective metadata records for the corresponding logical identifiers; storing the logical identifiers and the base types in an ID registry; and defining associations between the logical identifiers and the base types.