NES 8-bit - Cartride based (games already in memory).
SNES 16-bit ditto.
N64 64-bit ditto.
Playstation, 32-bit, 2Mb Memory (2048bytes)
PS2, 128-bit, 8Mb memory (approx 8200bytes)

My PC has 1gb memory - cost me £1250.

The more memory (in M the more information can be LOADED onto the console. The game itself with the X-Box and the PS2 are both DVD (the same), I think gamecube is DVD as well, but I don't know anything about gamecube.

The more bitage the broader the machines chip-to-chip information passage 'bandwidth is'.

Memory isn't that important as long as you can push the polygons fast (which is graphics card based).

The cufusion arrives from cartridge based systems whose size was measured in Megabits - don't ask.

The more important statistic with these new consoles is the polygon pushing rate. Beware of consoles giving the push rate for different types of polygons.

Anyway they could all probably cope with the new Final Fantasy game which I think will be excellent. I've played every one so far, and my favorites are FFVII and Final Fantasy 5 (or 2 for the American release). I just hope the plot is as good as FFVII or FFIX, because I didn't like FFVIII that much (why did she want to compress time anyway?)