Yes, the 3DS are backwards compatible.
Yes, Nintendo DS Games are backwards compatible with the Nintendo 3DS Wrong they are not
The Nintendo DS is fully backward compatible with Nintendo DS games; however, the Nintendo 3DS does not have Slot 2, as seen on the Nintendo DS and Nintendo DS Lite, so those features will not be supported. Additionally, DSiWare games will be available to download on the Nintendo 3DS after the software update in May 2011.
The Nintendo 3DS will be able to play Nintendo DS and DSi games but games published for the Nintendo 3DS will not be compatible with those systems.
The Nintendo 3DS is backwards compatible with Nintendo DS titles, so all DS Pokemon games and subsequent 3DS Pokemon games will work on the 3DS.
Yes, the 3DS will be backwards compatible with the DS, but the standard DS games will not be in 3D.
No the 3DS game cards are shaped slightly different then the Nintendo Ds. Of course if you could put the 3DS game cards in the Ds lite it would still not work because the features and intense graphics the nintendo 3DS requires for games can't be used on the Ds lite. Don't buy 3DS games for the Ds lite as it just won't work. You can consider buying a 3DS however as the 3DS is backwards compatible with all DS games.
No. The Nintendo 3DS has it's own selection of 3DS games but it can still play Nintendo DS and DSi games. Also, the Nintendo eShop has a Virtual Console which allows you to play games from the NES, N64 and GameBoy.
Yes, the Nintendo 3DS (as well as the 3DS XL and 2dS) has its own 3DS games that will not work for the Nintendo DS, Nintendo DS Lite, Nintendo DSi, and Nintendo DSi XL.
Yes, the 2DS can play Nintendo 3DS and DS games
Yes. The 3DS, 3DS XL and 2DS are backwards compatible and can play DS and DSi games. Unless they require the GBA slot, the 3DS is not compatible with Slot 2 attachments for the DS so games such as Guitar Hero will not work. The DS and DSi game will not be in 3D even if the 3D is turned on.
3DS games cannot be played on a DS lite. You need a console from the 3DS family - 3DS, 3DS XL, 2DS, New 3DS, New 3DS XL.