When you purchase an Xbox you get along with it a catalog which has details about the version as well as the working of the product. So after going through the details you will be able to determine the version.
Where Did The Xbox 360 Come From?
The Xbox 360 is the descendant to the Microsoft's Xbox video game console, created in collaboration with IBM, ATI, Samsung and SiS. Details about the console initially came via viral marketing campaigns and it was formally made public on MTV on May 12th, 2005, with in depth launch and gaming information revealed extensively shortly that month at the Electronic Entertainment Expo.
What's So Special About The Xbox 360?
The Xbox 360 is the foremost console to be launched near-simultaneously transversely in three main regions, it was also the first to offer wireless controller on its release.