Okay so, I'm reasonably well connected to the world. What can Facebook offer me? I don't use it, I have never had an account, and I always thought it was a fad

Okay so, I'm reasonably well connected to the world. What can Facebook offer me? I don't use it, I have never had an account, and I always thought it was a fad. It seems that it has taken awhile, but the world has agreed it was a fad and it is now over it. So, what did I actually miss out on?