Information Technology Reference
In-Depth Information
Equivalence
Complementarity
Backend
system
Complementing information
C
B
D
Printed
representation
Digital
representation
A
A
Backend
system
A
Backend
system
Fig. 3.9
The two principles of how information is related between different representations
EQUIVALENCE
COMPLEMENTARITY
single
multiple
one single piece
of information
several complementing
pieces of information
multiple
single
multiple representations
one single representation for
each piece of information
Fig. 3.10
Distinctive features of the two principles
Complementing information serves two main purposes. First, complementing
pieces of information can provide the user with updates of a piece of information.
While it is usually preferable to directly update the representation of the piece of
information the user is working with, this is not always possible. For example, a
digital system cannot update information on paper in real-time. However, real-time
updates are possible with a complementing digital representation, such as a projec-
tion that overlays the printed document.
Second, complementing information can provide different pieces of information
on a second channel. For example, if the user works with a printed representation
of a Web page which contains background music, a complementing digital channel
