As per Wikipedia Second Life is an online virtual world, developed and owned by the San Francisco-based firm Linden Lab and launched on June 23, 2003. It saw rapid growth for some years and in 2013 it had approximately one million regular users; growth stabilized and by the end of 2017 active user count had declined to "between 800,000 and 900,000". In many ways, Second Life is similar to massively multiplayer online role-playing games; nevertheless, Linden Lab is emphatic that their creation is not a game: "There is no manufactured conflict, no set objective".
Now, Secondlife to me...well it is so much more. You can be anything! Furry, BDSM, Vanilla, Raver, Gorean, and so so much more.
I started Secondlife on a whim almost 14 years ago. That's right I am an OG of Secondlife. I have seen so much come and go. It lets the people who normally struggle with face to face interactions over come their shyness or their inability to actually be in large groups. No fear of someone touching you or jostling you at a club while there because you can just teleport out.
We whom stayed in SL as we know it, have dealt with rolling restarts, character changes, flexi, and mesh. Now BOM (baked on mesh) is a new thing and we are all on a learning curve.
This is truly a place you can be whomever you want, explore whatever and where ever you want as long as you stay respectful.