As in most First Person Shooters, the controls exist of both mouse and keyboard.
Basic Controls The player can move around with the W, A, S and D keys (can be re-configured) and looks around with the mouse. Clicking the left mouse button fires the weapon, and the right mouse button is for the alternate fire (e.g. putting a grenade on the M1 garand, so it can be fired and the grenade will fly further). Special actions, like opening doors and disguising as an enemy player, can be done by pressing the F key. Leaning to the left and right can be done by pressing the Q and E keys. To change stance, players can use C to crouch, and Z to prone. The spacebar will make the player jump / change position back to stand if proning. The player can use the L key to open up the Limbo menu. In the Limbo menu, players can configure which class they want to be and the weapons they want to use when they respawn.
Voice-chat By pressing V, the player can use voice-chat. These are faster than chatting and don't require a microphone. Some examples are 'I need a medic' if the player is badly wounded, 'I need ammo' if the player is running out of ammunition, but also greets and cheers.
Chatting A player can write messages to the other players in the server by pressing either the T key, the Y key or the U key (which can, of course, be re-configured). If the T button is pressed, the player can send a message to all the players in the server. If the Y button is pressed, a message can be sent to all teammates. And finally, if the U button is pressed a message can be sent to all fireteam members.