Blu-ray is similar to the DVD but is capable of storing high definition video resolution (1080p). Blu-ray was made to get rid of DVD's like DVD's did to VHS but it has not worked the way that company's wanted and has only really keep up with DVD's.
Blu-ray players have been added to gaming console like Xbox One and both PlayStation 3 and 4 giving people the chance to watch Blu-ray with out having to buy a Blu-ray player.
People have been working on the Blu-ray since 2000 when it was first shown to the public and then in 2006 it was first sold but didn't really get the profit that was expected of it.
Sales have gone up since 2006's 1.2 million to 2010's 350 million which a big difference.