Spotify, with a hi-fi knob: your own radio station in 1962

Spotify is what happens when the old radio pitch becomes private, portable, and uncannily well acquainted with your Tuesday mood.

In the 1950s, advertisers began treating teenagers as an age-defined market. The Smithsonian's National Museum of American History says marketers studied their buying habits and built campaigns around music, magazines, clothing, and rituals like the high-school prom. 1

Transistors made radios smaller and more portable, letting young consumers take music with them; the Smithsonian illustrates the point with an RCA Globe Trotter 8 radio from about 1956. 2 Commercial radio had already trained the living room to accept a friendly voice advising what to buy. 3

Spotify's official timeline says it was founded in April 2006, launched in Finland, France, Norway, Spain, Sweden, and the U.K. in October 2008, and introduced personalized recommendations with Discover Weekly in 2015. 4

That makes the spoof click: Spotify is the radio, the record store, the teen-magazine taste-maker, and the slightly smug friend who says, "I know what you'll like"—all in one pocket.