1. An integrated input/output device for a computer system having a primary display, the integrated input/output device comprising: a plurality of alphanumeric keys for receiving character inputs from a user; an input-sensing display device configured to provide displays supplemental to the primary display of the computer system and to receive display selection inputs from the user, the input-sensing display device positioned proximate the plurality of alphanumeric keys, wherein the display selection inputs correspond to possible correct text units of text displayed on the primary display; and a display device interface configured to provide the display selection inputs to the computer system and to receive supplemental display data for displaying on the input-sensing display device, wherein the input-sensing display device is removable from a first structure at the display device interface, the first structure including the plurality of alphanumeric keys, the display device interface operatively connecting the first structure and the input-sensing display device when connected with each other, wherein the input-sensing display device comprises a computing device having functionality independent of the integrated input/output device.