Connected: An Internet Encyclopedia
13.13 History Lists

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13.13 History Lists

13.13 History Lists

User agents often have history mechanisms, such as "Back" buttons and history lists, which can be used to redisplay an entity retrieved earlier in a session.

History mechanisms and caches are different. In particular history mechanisms SHOULD NOT try to show a semantically transparent view of the current state of a resource. Rather, a history mechanism is meant to show exactly what the user saw at the time when the resource was retrieved.

By default, an expiration time does not apply to history mechanisms. If the entity is still in storage, a history mechanism should display it even if the entity has expired, unless the user has specifically configured the agent to refresh expired history documents.

This should not be construed to prohibit the history mechanism from telling the user that a view may be stale.


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Connected: An Internet Encyclopedia
13.13 History Lists