An S-Video-to-Scart-adapter has on one side an S-Video- (for the picture) and two Cinch-connectors (for the sound) and on the other side a Scart-connector (which is plugged into the TV or the video recorder).
If you want to watch your computer screen on your TV, you take an S-Video cable, plug one end into the TV-Out of your graphic card and the other end into the adapter. Then you take this adapter, switch it to "Input", and plug it into the TV.