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User agent

Software acting on behalf of a user

On the Web, a user agent is a software agent responsible for retrieving and facilitating end-user interaction with Web content. This includes all web browsers, such as Google Chrome and Safari, some email clients, standalone download managers like youtube-dl, and other command-line utilities like cURL.

The user agent is the client in a client-server system. The HTTP User-Agent header is intended to clearly identify the agent to the server. However, this header can be omitted or spoofed, so some websites use other detection methods.

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Sources and credits

This article is adapted from the Wikipedia article User agent, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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