This is the largest list I know of (~176): https://ryanschultz.com/list-of-social-vr-virtual-worlds/ https://ryanschultz.com/list-of-social-vr-virtual-worlds/

This is the largest list I know of (~176): https://ryanschultz.com/list-of-social-vr-virtual-worlds/ https://ryanschultz.com/list-of-social-vr-virtual-worlds/ But it's missing many. Others have already mentioned Habitat (1986). Probably one of the most important.