Among the people I know still using Last.FM, it's somewhere between having statistics about your music, and a recommendation engine. It isn't about playing the music, you can do that elsewhere. But by having data on every single piece of music you've listened to, it can recommend music you will like, and potentially recommend people with shared musical tastes as well. There's a feature to compare your musical compatibility with others.

For me, many years ago Last.FM recommended this weird electronic band that I'd never heard of, with the strange name "Boards Of Canada". That Last.FM recommendation was responsible for introducing me to my 2nd most listened to band of all time (just behind NIN). 2026 is many hexagons, dandelions and an inferno later.

Originally, it kind of worked like radio; it curated music for you, you could like, comment or skip tracks. It'd reinforce the algorithm, and you'd start finding great artists. I liked the Blues catalogue a lot, even though I was listening to reggae, ska, punk, etc. It just seemed they had the best music catalogue. I remember checking how big the catalogue was, comparatively with others, which was much smaller, but much, much better!

Today, we have Generative AI, generating an incomprehensible number of songs that no one will ever listen to.

I don't remember if I had to pay for Last.fm or not back then, but I'd definitely pay to have access to that old system.