There is nothing to be compatible with. Wireless A (IEEE 802.11a) was the first standard of the IEEE 802.11 standard.
Yes, it is.
Yes, a wireless n adapter is backwards compatible with wireless g. Check the box you are buying and it will tell you if it is compatible with which wireless ranges.
Yes it is backwards compatible
Backwards compatible on 360!
Sort of. Almost all Wireless N routers support the G protocol aswell, so will be compatible with these devices. Whether they benefit from the extra range, I do not know.
If you PS3 is not backwards compatible nothing you can do will change that
yes
First Generation models ie. those that were released first were fully backwards compatible and played PS2 and PS1 games as well as PS3 games. The second generation of the PS3 also which also had 4 USB ports were also Backwards compatible with many of the PS2 games. All other PS3 models lack the backwards compatible feature and are not considered to be Backwards compatible. see related link.
Wireless B runs at 11 mbps, and wireless G runs at 54 mbps. Wireless G supports frame bursting, and many other features that were added after B came to be, but G is backwards compatible with B networks. However, a G network will experience performance hits when B clients are connected.
All ps1 games are playable on ps3, so Metal Gear Solid 1 is backwards compatible, but only backwards compatible systems can play the second and third game on ps3.
The wireless Beats by Dre are compatible with any device that can send audio over Bluetooth.
Yes it is.