Kart Kingdom uses servers to allow players to play with other players. There are seven servers (If you include Server 7). The menu usually only shows a few servers. The servers are Pine, Sodor, Birdwell, Wagstaff, Elwood, Server 7, and Reeftown. They are named after locations in shows on the PBS Kids channel (Except for Server 7).
Occasionally, one or more of the little people icons will be green. This didn't happen for almost two years after the beta but happened for just one minute on October 16, 2017. The event was documented by SirGawain8. It is unknown why this happens, and ever since then, the little green people appear almost every day.