: Refers to the resolution of the video. It means the video has 1,080 horizontal lines of vertical resolution, often referred to as "Full HD."

: Video editing software may use "1080p" as a default export preset name if a project title isn't specified.

: Many YouTube or social media "downloader" tools save files using the resolution as the default name.

To help you figure out what's actually inside that file, could you tell me: Where did you it from? Are you trying to open it , or Is it a corrupted file you're trying to fix?