Radio asks less of your attention than any other medium. You do not have to look at a screen, you do not have to pick a title, and no algorithm demands a decision from you every five minutes. That is exactly why radio has survived the on-demand boom instead of being erased by it: the two formats serve different needs.

Technically, the stations here take two routes. Most broadcast a continuous Icecast or SHOUTcast stream in MP3 or AAC, which the browser's audio element plays directly. Others, such as the BBC, have moved to HLS audio, where the broadcast is cut into short segments exactly as it is for television.

Radio is also remarkably light on data. A 128 kbps stream uses roughly 58 MB per hour, and a 256 kbps stream about 115 MB. That makes it the safe choice when your data plan is running low but you still want something in the background.