Comparison of gaming platforms

PC - Input
Modern PCs can essentially use ANY input device, as long as there's an adapter to convert it to USB. The problem is, only software built to intentionally accept any type of input signal will accept this. Modern games, for example, probably won't work with a USB-adapted NES controller. Emulators (such as Project64 on the other hand, accept input from almost anything (even mixing between several input devices).

Xbox 360 - Backwards Compatibility
Via software-based emulation, there is a backwards compatibility rate of 51% of 461 for first-gen XBox1 games. Network functionality not emulated.

Platforms in Competitive Gaming
All platforms support competition in some form. The Space Invaders Championship held by Atari in 1981 was the earliest large scale video game competition. Players would compete for the highest scores.

The tournaments which emerged in the mid 1990s coincided with the popularity of fighting games, played in both arcade machines and video game consoles. In the late 1990s, broadband internet paved the way for first-person shooters tournaments on PC, the most notable being the Red Annihilation tournament in 1997 where Dennis "Thresh" Fong won John Carmack's Ferrari. In the early 2000s, real-time strategy games on PC became overwhelmingly popular in South Korean internet cafés, with crucial influence on the development of competitive gaming worldwide.

As of August 16, 2014, the largest platform for competitive gaming is PC, with the games Dota 2, League of Legends, StarCraft II, and Counter-Strike: Global Offensive. Over $21 million has been awarded in Dota 2 competitions. Fighting Games and the latest iteration of the Call of Duty series are popular on consoles.