There is no limit to how many people will be allowed in our universe simultaneously. New space stations and solar systems will be discovered in order to account for the amount of people playing. Every player will have one character that can be customized. You can choose between three different races. And for every race there will be several different bodies to choose from.
Every character also has a rank.
Every character will own one spaceship. You will be able to use it to fly to different space stations or planets in order to communicate with other players. When you walk around with your character, you will see the world in a 3rd person perspective. When you fly your space ship, it will be first person. Depending on what civilization you choose, your rank will increase either by fighting or by trading.