It hardly matters now, but just two years ago Microsoft were at the butt end of gamers' vitriol for their then-controversial policies regarding the Xbox One. If implemented, they would essentially have turned it into an all-digital gaming box not too dissimilar to a Steam-powered PC (why gamers were so on to Steam while dissing the Xbox still escapes me), and naturally, they took some pretty painful, albeit hilarious jabs from their closest competitor. Sony, with the Playstation 4, jumped on the bad press and has been having the players' favor ever since (Xbox just very recently was able to turn the tide).
Fast-forward to today, however, and it's clearly seen that while PS4 still has the sales lead, Xbox One is the better listener, churning out great new features according to fans' requests, the biggest of which has to be Backward Compatibility for the Xbox 360, something sorely lacking on Sony's console. Xbox finally has the ammo, and they just shot back at Playstation with the latest tutorial video for Backward Compatibility.
The video, striking it its simplicity, serves as a good introduction to how Backward Compatibility works on the Xbox One while answering some frequently asked questions. If you feel it's somehow familiar, however, then know that it is, as the format closely mimics one of Sony's videos in which they depict "physical" game sharing on the PS4, down to the "steps" and the lengthy intro music.
Of course, there are a bit more steps to getting your Xbox 360 on your Xbox One digitally than just giving your friend a disk (by the way, physical Xbox 360 discs works just as well), but overall, it's a nice joke and light tease that shows the Xbox team's confidence in their work: after all, we as consumers will benefit the most from some healthy competition.