This is the definitive "longest" version of the movie. It includes 16 minutes of additional footage not seen in theaters, such as an opening sequence on Earth and a scene involving a massacre at a Na'vi school.
The string refers to a specific digital release of James Cameron's 2009 film Avatar . Each part of this label provides technical details about the video file: subtitle Avatar.ECE.2009.720p.BrRip.x264.bitlok...
Short for "Blu-ray Rip," meaning the file was encoded from a retail Blu-ray disc source. This is the definitive "longest" version of the movie