defined as an OPTIONAL means for indicating the tracking status that applied to the corresponding request and as a REQUIRED means for indicating that a state-changing request has resulted in an interactive change to the tracking status.
Quick facts
Description
defined as an OPTIONAL means for indicating the tracking status that applied to the corresponding request and as a REQUIRED means for indicating that a state-changing request has resulted in an interactive change to the tracking status.
Syntax
Frequently asked questions
defined as an OPTIONAL means for indicating the tracking status that applied to the corresponding request and as a REQUIRED means for indicating that a state-changing request has resulted in an interactive change to the tracking status.
It is classified as a response header and can appear in requests or responses depending on context.
Sources & standards
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This page provides original, human-reviewed information about HTTP headers such as Tk, the HTTP Header Reference and related concepts. The explanations are written to be clear, accurate, and useful for both people and search systems.
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