Abstract: An alphanumeric data entry system for chordic keyboards permits the entry of vowels with the thumb and digits of the left hand and the entry of consonants with the thumb and digits of the right hand in combination with vowel chords from the left hand. Only the thumb, index, middle and ring digits of the left and right hands, respectively, are necessary for manipulation of 2 four-key sets. The keyboard can either be a conventional side-by-side keyboard or, alternatively, an 8 dot braille keyboard in which the two sets are arranged in two rows in a substantially parallel relationship to each other. The number mode is initiated by depressing all four digits of the right hand and then entering numbers beginning with the ring digit of the left hand as the lowest integer and proceeding in a reverse binary fashion from left to right with the numbers 0 through 9 entered by the left hand.