Password entry is done by displaying to a user distinct codes corresponding to characters in the user's password. The user then serially enters codes corresponding to characters while concealing the entry. Only a limited number of keys are used for password entry. In one example, two keys, a "HIT" key and a "NEXT" key, are provided within a concealing hood, and the password in entered serially as a number of "HIT" key hits. The user is prompted to enter digits corresponding to symbols of his or her password with a display of unique m-ary number codes assigned mutually exclusively to different characters. The scheme can be easily implemented in existing computer systems entirely through a conventional ASCII keyboard or mouse, by using adjacent keys on the keyboard or left and right mouse buttons. As the method requires only a few keys, concealing the keys to prevent viewing of key entry is possible.