The string is a standard naming convention used in file-sharing communities: : The title of the film and its release year. 1080p : The video resolution (1920x1080 pixels).

This was captured from a streaming service. Unlike a "Web-DL" (which is a direct file download), a WEBRip is re-encoded during the capture process. However, at 1080p, the visual quality remains very high, usually indistinguishable from the source for the average viewer.

Indigo.2016.1080p.WEBRip.x264.AAC.HORiZON-ArtSubs