User Agent

Definitions

1. An HTTP header string that identifies the client software making a request, traditionally including the browser name, version, rendering engine, and operating system. Decades of browser-war spoofing have made most user-agent strings comically long chains of compatibility lies.

   In plain English: A label your browser sends to websites identifying itself, though years of faking have made these labels almost meaninglessly long.

   Example: "Every user-agent string starts with 'Mozilla/5.0' for historical reasons, even Chrome and Edge."

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