Apple Inc. AAPL 0.78% launched its music-streaming service in 2015 a year after buying Beats Electronics LLC. Its debut stumbled over user interface and engineering problems, but the service was revamped within a year and quickly became the No. 2 on-demand service. Apple's iTunes, where customers pay to download individual songs or albums and own them permanently, is separate but accessible through the platform. Apple Music has benefited from its integration with Apple devices, from iPhones and MacBooks to Apple Watches and HomePod voice-activated speakers, which sync easily with Apple Music but less so with Spotify or other services. Apple Chief Executive Tim Cook has said streaming isn't a moneymaking business but has emphasized the importance of providing music and supporting artists.

If you're a folk rock fan like me, you might be surprised when a music-streaming service suggests songs for you in other genres, such as country or reggae--and you actually enjoy them. Apple Music, Pandora, Spotify, and similar services are taking subtle cues from your listening habits, not only to recommend new artists but also to create personalized playlists for you with tracks you've likely never heard before. To understand the technology making that possible, The Institute spoke with IEEE Member Josh Perline, a software engineer at Pandora. Perline is responsible for content personalization, which involves using data analytics and machine learning to automate the creation of suggested playlists. As one of the first music-streaming services on the market, Pandora has some 17 years of data to work with.

Music streaming app Spotify launched in Japan Thursday, making its official debut in the second-largest music market in the world about 18 months after it set up an office in Tokyo. Daniel Ek, CEO of the Swedish company, held a press conference in Tokyo where he announced two version of its service: a free one with ads and the other for 980 yen ( 9.7) a month. Ek added that the service will also be available through the popular PlayStation video game consoles, manufactured by Japan's Sony Corp, Bloomberg reported. However, the music market in Japan -- estimated to be worth about 3 billion -- may prove to be a tricky one for Spotify, as it has been for most music streaming services that operate in the country, given that CDs are still the most popular format for music sales. The continuing popularity of conventional physical formats of music storage, including vinyl records, was one of the reasons for Spotify to delay its launch there.