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Spotify is a playlist-oriented music streaming service offering music from a range of major and independent record labels, including Sony, EMI, Warner Music Group, and Universal.
SpecsUpdate
Pros
Pro Streams from a huge collection of music and gives fast access to newly released songs
Spotify has over 20 million songs and arguably the largest collection out of all its competitors. It also usually has the among the fastest access to new music.
The Spotify desktop client allows local music files to be imported with the option of syncing with a mobile device which largely mitigates the issue of missing artists.
Cons
Con Spotify Premium required for uninterrupted listening
If you want to avoid your music being interrupted by ads, you have to pay a monthly subscription in order to obtain Spotify Premium.
Con Missing features of stand-alone players
Spotify works only as streaming software, but not as a conventional media player. It doesn't have any equalization tools nor does it have support for playing CD's.
Con Not a music player
Spotify is a music stream client not a music player like other options.