Wearable computer system

A computing device comprising:

• a user interface device comprising
• a first portion comprising a first set of keys on a first anterior surface;
• and
• a second portion comprising a second set of keys on a second anterior surface,
• the second portion hinged to the first portion for relative rotation substantially within a plane determined by the first and second anterior surface between a first mode and a second mode;
• wherein
• in the first mode the first and second sets of keys face away from a user's torso and are arranged in a first keyboard presentation to receive input from fingers of the user from a left side and a right side of the first and second portion with the first and second portion suspended in front of a user's torso in a substantially vertical position, and wherein
• in the second mode the first and second sets of keys are arranged in a second keyboard presentation to receive input from fingers of the user from a front side of the first and second portion with the first and second portion placed on a substantially flat surface in front of the user in a traditional, substantially horizontal keyboard position, and wherein
• the relative rotation substantially within a plane determined by the first and second anterior surface establishes a transition between the first and second keyboard presentations, and wherein
• the first and the second keyboard presentations are configured to enable operability of the same keys by the same fingers of the user in the first mode and the second mode;
• the computing device further comprising
• a processing unit coupled to the user interface device to receive user input;
• and a head-mountable display configured to provide a view of the functional assignments of the first set of keys and the second set of keys, wherein the head mountable display is capable of providing a posterior view of the first set of keys and the second set of keys in the first mode with keys facing away from the user.