The Others is a place holder. It is for any magical/highly advanced species that sometimes interacts with humanity. Who The Others are is determined by the setting. Some options are:
Elves, as most people know them, are the minimum level for being Others.
The Fey Shidhe would count possibles. They are near demi-gods.
The Mythics that I proposed would be good options.
The Science Fiction "Elders" or "Ancients" are good canidates.
There are more. In short, "The Others" is just a variable that you, the GM, need to fill in.