LA Weekly compiled a wonderful list of ambient albums that will serve as a perfect primer for the uninitiated, or as a trip down memory lane for those who heard some of this performed live. Several are on my permanent read/study playlist, like Eno's Ambient 1: Music For Airports.
From reviewer Jonny Coleman:
In 2015, ambient is most often found in private settings or art-related spaces: museums, galleries, college concert halls. But once upon a time in the '90s, chill-out rooms playing ambient music at raves and electronic music festivals were common. By the late '90s, that scene had receded into the background, but the 21st century has seen the rise of many new voices in ambient: Fennesz, Oneohtrix Point Never, Colleen, Emeralds, Rashad Becker, Holly Herndon, Grouper, Dalhous, Bing & Ruth, Nils Frahm, and many more.