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Everything about User-Agent header

Type of data transmitted by a web browser

In computing, the User-Agent header is an HTTP header intended to identify the user agent responsible for making a given HTTP request. Whereas the character sequence User-Agent comprises the name of the header itself, the header value that a given user agent uses to identify itself is colloquially known as its user agent string. The user agent for the operator of a computer used to access the Web has encoded within the rules that govern its behavior the knowledge of how to negotiate its half of a request-response transaction; the user agent thus plays the role of the client in a client–server system. Often considered useful in networks is the ability to identify and distinguish the software facilitating a network session. For this reason, the User-Agent HTTP header exists to identify the client software to the responding server. Wikipedia →

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  1. Read the overview: User-Agent headerA 5-minute orientation
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  3. Go sideways: List of HTTP header fieldsA closely related topic
  4. Go sideways: Gecko (software)A closely related topic

đź“– Definitions

No dictionary entry for this exact phrase.

🗂️ The subject at a glance

  1. Use in client requests
  2. User agent spoofing
  3. User agent sniffing
  4. Deprecation of User-Agent header

🏆 Landmark papers (most cited)

đź“š Books worth reading

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đź”— Related topics