PICS System Overview

There are any number of rating services who provide labels for information.
Each rating service uses a rating system (of its choice) consisting of one or more scales (or dimensions) to label information.
A rating service can label anything that has a URL.
Labels can be sent with a document or retrieved separately.
Labels can be created by the author of a document, the publisher of a document, or an independent third party.
End-users choose the rating service(s) whose labels they wish to use, as well as the particular values along the scales that they consider acceptable (or unacceptable).