In "One player" section you can begin new Campaign or continue already begun. Also you can play single mission in skirmish.
In "Multiplayer" section you can create network game to play with friends or will join to other players in internet on Warnet server.
In "Settings" section you can adjust graphic sound and game parameters.
In "Profiles" section you can change current profile. Probably it is required in a situation when one computer use many players. All settings and campaign progess will be saved under a player profile.
Section "Credits" about people who create this game.
Exit from game in operation system.
