Diffrence between D20 Modern and D&D 3.x

[ShadowFireLance]

What are they? It seems like the same game.. So Can someone tell me?
The Reason i Ask this is because I got a 40k D20 Modern one, And am Trying to use it with D&D 3.x.

[Urpriest]

D20 is a system, D&D 3.x is a (pair of compatible) games. They aren't even in the same category.

[ShadowFireLance]

But I see D20 Modern that looks like I can use it with D&D...Have I been reading it wrong?
Edit: Reviseing my question, I wrote it wrong.

[Lord Il Palazzo]

But I see D20 Modern that looks like I can use it with D&D...Have I been reading it wrong?It's built on the same system, so large chunks of it are compatible but it's still a different game with rules of its own that can and do work differently in places from D&D. (I've never played D20 Modern, but from what I understand the money system is quite different, for example.)

[nyjastul69]

I'm AFB right now but the first thought I had about is how the 2 games handle character health. D&D use HP's alone. d20 Modern uses wound and vitality points. It shouldn't be too difficult to mix and match the 2 games.

[Jeraa]

I'm AFB right now but the first thought I had about is how the 2 games handle character health. D&D use HP's alone. d20 Modern uses wound and vitality points. It shouldn't be too difficult to mix and match the 2 games.

No, it doesn't. It uses hit points just like D&D does.

[Larkas]

They are not directly compatible, but with a few minor tweaks, can be used together with very little effort. Check this Apocalypse Demon Unicorn (http://www.wizards.com/default.asp?x=dnd/eo/20061219a), for example.

[nyjastul69]

No, it doesn't. It uses hit points just like D&D does. Thanks for the correction. To the OP, sorry for the misinformation, I'm must be confusing it with some other d20 game.
Edit: d20 Star Wars is the game I was confusing it with.

[ShadowFireLance]

Oh, So not that much harder to change eh? Thanks!