A capture card is a device that facilitates the transmission of audio and video signals from a source (usually a game console or some other input) to a computer, where they can be recorded, stored, and streamed to other devices.
A game capture card is a device that enables gamers to record, stream and save their gaming sessions by capturing video and audio from gaming consoles such as Xbox, PlayStation and Nintendo Switch.
Capture cards allow you to record or stream in high quality from your computer, console or other device. Capture cards capture the video signal from your device, process it, and send it to streaming platforms like YouTube or Twitch.
It is worth noting that the capture card does not handle any data encoding. It simply simplifies the transfer of data from the input device to the computer, which then transmits the footage to the streaming platform.