I use Facebook, Twitter and Telegram. I registered on SteemIt but never got started with it.
Out of those, I mainly use Facebook to keep up with my childhood friends, co-workers, family and online friends (TMA/Team Fortress Classic). My ex shoved me into it about 9 years ago...once I cut ties with her and her douchebag friends, Facebook got cooler to me in certain ways. I enjoy the memes, mainly...and I do enjoy trolling people on there (just like the ancient TMA days, 2000-2002 era).
I mainly use Twitter to follow John McAfee and check up on cryptocurrency projects I have money invested in. Same with Telegram. Just to chat with team members connected to crypto.
I'll admit I miss MySpace a little bit. But for the love of God, the fucking load times were unreal. Almost every female on my friends list at that time had "Unwritten" by Natasha Bedingfield as their profile song...it was the original pumpkin spice latte.
...I don't know if anyone remembers Live Journal. I check on my old one once a year and slouch down in my chair in embarrassment.