A rectangular personal digital assistant (PDA) includes a rectangular housing
having
a front side facing towards users and four corners, a computer circuit installed
in the housing for providing data processing services, a socket installed in one
of the four corners and electrically connected to the computer circuit, and a peripheral
module having a case and an input/output peripheral circuit removably and electrically
connected to the socket. When the peripheral module is installed in the socket,
the case of the peripheral module coupled to the corner of the PDA housing will
form an integrated corner of the PDA housing.
