Can someone specify the stages of play for me? Are they way off?

My daughter is supposed to be in the ”solitary” stage where they just play near each other and not with each other. At one year she seemed to be in the spectator stage. Apparently, they're not supposed to understand the concept of sharing, but my 18 month old shares and actively engages other kids that she likes with toys and by gently touching them on the arm to get their attention. She likes to play tag with others too. She has a preference of friends...there are some she doesn't interact with and others she loves and wants to be around. I basically don't exist when there are other kids around. Are these charts way off like some of the milestones where some meet each faster or slower than normal? Or is my daughter just way more social? I don't get it.