Plug in your external webcam and wait a few seconds for your OS to detect it. Open an online webcam test and use the device dropdown to select the external camera instead of your built-in one. The preview should show the external camera's feed with resolution and FPS info. If the webcam doesn't appear in the dropdown, try a different USB port, avoid USB hubs (plug directly into the computer), and check that no other app is using the camera. On Windows, verify the camera appears in Device Manager > Cameras. On Mac, check System Settings > Privacy & Security > Camera. Most external webcams are plug-and-play on modern systems, but some high-end models need manufacturer software (like Logitech Tune for Logitech cameras) for full feature access and firmware updates.
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