Condition (2) sets information customization apart from traditional information filtering and retrieval,while (4) sets it apart from client-side agency,and (5) would distinguish it from traditional nonlinear document traversal systems (e.g. hypertext).

• 条件（2）将信息定制与传统的信息过滤和检索区别开，而条件（4）将它与客户端的代理区别开，条件（5）使它与传统的非线性文档遍历系统（如超文本）相区分。