Recording console video game plays on the PC?

I've seen several videos of people who've recorded how they were able to complete video games at a fast speed, but how were they able to record it to the PC in the first place? Do they use something like a TV tuner card? I had one before and I did try to connect my PS2's video-out into the video-in port but the picture, while ok, was nowhere near as clear as those other videos I've seen.

What hardware do they use to capture video from something like a console system and record it on the PC?