The resolution. It’s "High Definition," but on the lower end compared to 1080p or 4K. It looks great on a phone or tablet, but might look a bit soft on a giant 4K TV.
In short, this file represents a very specific era of a movie's lifecycle—the moment it leaks in decent quality just before the official digital or physical home media release.
The compression codec. It’s the industry standard for shrinking movie files down to a manageable size without losing too much visual detail.
The audio format (Advanced Audio Coding). It’s a standard, high-quality stereo sound format that works on almost any device.
This stands for "Hardcoded English Subtitles." Unlike "soft" subs that you can turn off, these are burned directly into the video frames.