Minecraft Realms is a paid service by Mojang that allows users to easily host a "Minecraft” server. Hosts who subscribe to the service can select which players they wish to invite and only those players can access the server.
Minecraft Realms allows a host to invite a maximum of 20 players to the server with a total of ten users playing at any time. Using Minecraft Realms is simple, but it costs a monthly fee. Modding and using older versions of "Minecraft" are not supported. Minecraft Realms does allow importing and exporting of maps, command blocks and most admin commands.