As of 2014, Stephen Hawking speaks with the assistance of a computer-based communication program called EZ Keys. A cursor on his screen continuously scans across a keyboard, and Hawking can stop the cursor on a character by moving his cheek.
His cheek movements are detected by an infrared sensor mounted on his eyeglasses, and he can spell words one character at a time in this way. The use of this sensor is the only way that Hawking can interact with his computer. The EZ Keys program includes an auto-complete function that allows Hawking to type the first few letters of a word and then select possible words from a list. Once he has built a sentence on the screen, he sends it to a speech synthesizer that communicates his message audibly.