Layering and User Interface

Owners of various layers have different responsibilities and constituencies

• Five Logical Layers (and responsibility)
  1. user experience - no one and everyone.
  2. user interface - implementers.
  3. recommended setting -  consumer advocates and other parties trusted by users.
  4. grammar - W3C.
  5. vocabularies - IPWG and others.
• Example questions: where is the concept of a child represented?

Must be explicit about scope, and sometimes provide hints or recommendations to other layers.

Cranor and Reagle