My musical tastes vary from rock and it’s many subgenres and off shoots to dozens of genres of EDM (mainly Progressive House, Trance, Techno, Psytrance, Dubstep, and Drum & Bass). I have a Spotify library exceeding 12k tracks.
Some of my favorite acts in no particular order include The Offspring, Rise Against, Pearl Jam, Ghost, Led Zeppelin, Iron Maiden, Avenged Sevenfold, Red Hot Chili Peppers, Breaking Benjamin, Billy Talent, Linkin Park, Paramore, Deadmau5, Feed Me, Kill The Noise, Liquid Stranger, Dance With The Dead, Ghostland Observatory, Rezz, Eric Prydz, Infected Mushroom, Heatbeat, Death On The Balcony, Hernan Cattaneo, and Lee Burridge just to name a few.
Yup! Those websites are the instances which are the infrastructure and interface by which you can access communities - each of which is hosted on a specific instance. An instance is essentially the collection of all the communities it hosts and all of the users signed up through that instance.