This is the end result when you complete the 20 glyphs found throughout the game.
Binary Code at end of video:
01000101=E
01000100=D
01000101=E
01001110=N
==EDEN
Nothing is true, everything is permitted.
-----SPOILERS BELOW-----
If you beat the game, and did the glyphs, you would understand this video.
But, if you're not going to do that, here's an explanation.
Strictly speaking, it isn't just a video. It's a memory, as recorded by the Animus. This means that Subject 16 must be a descendant of Adam. Not figuratively, but born of Adam's genetic ancestry.
The memory reveals that the story of Adam and Eve and the Garden of Eden is true - in a fashion. It would appear that they disobeyed their masters and strove to rebel by stealing a Piece of Eden, an Apple, presumably to give themselves some kind of defense or power to resist. This could have been the first act of defiance that led to the conflict described by Minerva. The "innocence" of humankind was lost when we realized how much of their superiority lay in their technology, and a war between the two species, First Civilization and humans, began.
Subject 16's record also shows that the artifacts, the Staff, the Apple, the Pieces of Eden, were tools that the First Civilization used to wield power over humans. Whether the artifacts were made to control humans, or humans were made to obey artifacts, is another matter. Even so, some are immune to their effects.
Moreover, the Glyph puzzles give hints to the involvement of Pieces of Eden in world history. Famous figures and crucial events may have been shaped by the influence that the technology can exert.
