Information about capture cards and how to use them

Hi guys, i usually record PC games using fraps and it got me thinking to how do people record console footage and then put it on the computer.
The problem is i dont know the first thing about gaming capture cards and how they work, i do know however that some of them are PCI cards.

so a couple of my questions are.
1. if a console is connected to a T.V how is the footage captured from the console to a PC?
2. Does using capture cards also provide audio or do you need certain cables (3.5 jacks, hdmis, etc)

i will probably have more questions when these ones are answered

Thank you in advance!

Hey,

I used to have a Partnered YouTube Channel, Where I would commentate and capture Call Of Duty gameplay.

The hardware I used was a HD PVR from Hauppage. http://www.play.com/PC/PCs/4-/7791395/-/Product.html They retail at around £120.00

How they work:

Your console (ps3/Xbox) connects to the PVR (IN channel ) Then the PVR has a "out channel" Which connects to your TV,

Then there is a USB, that connects the HD pvr to your pc,

Yes, The PVR will also do audio, and no extra cables are required for this.

Install the software that comes free with the Hauppage PVR, and your good to go,

Id recommend making sure you have a graphics card with at least 256mb ram.

Hope this helps.

hey i need more information,
this pvr bx suggested by braddersz, would it work with older consoles, like SNES n64, ps1/ps2 etc?