Pen-based systems—including many tablet PCs, personal digital assistants, and
other types of handheld computers—use a pen for data input (see Fig. 1
Fig. 1: handheld computers—use a pen for data input.
This device is sometimes called a stylus.
You hold the pen in your hand and write on a special pad or directly on the screen.
You also can use the pen as a pointing
device, like a mouse, to select commands by tapping the screen.
You might think that pen-based systems would be a handy way to enter text into
the computer for word processing. In reality, developers have had a great deal of
trouble perfecting the technology so that it deciphers people’s handwriting with
100 percent reliability.
Because handwriting recognition is so complex, pen-based
computers are not used generally to enter large amounts of
text, although they are used
frequently for taking notes,
creating short messages, and
writing annotations on electronic documents.
PDAs and tablet PCs
are popular for these kinds of tasks, which do not require keyboarding.
Pen-based computers are
commonly used for data collection, where the touch of a
pen might place a check in a
box to indicate a part that
must be ordered or a service
that has been requested.
Another common use is for
inputting signatures or messages that are stored and
transmitted as a graphic image, such as a fax. When
delivery-service drivers make
deliveries, they often have recipients sign their names on
such a computer-based pad. As handwriting-recognition technology becomes increasingly
reliable, pen-based systems
will undoubtedly become