Information Technology Reference
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of data. When the user types on a keyboard, the user is entering
data. Additional information has no inherent meaning to a user, a
program, such as Microsoft Word or StarOffice, may include
instructions about how to interpret that information. Other data
might include font descriptions that give information about the
form of each character—perhaps in normal appearance, italics, or
bold. As this example illustrates, data may come from either of two
initial sources: the user or the application itself. To explain these
sources further, data coming from a user consists of information
exactly as typed. Application data includes data supplied by a pro
gram. This might include information about initial fonts or spacing
in a document. If the user specifies what type of font to use, then
obviously that information has the user as its source. However, if
the user does not supply that information, then the program must
make some choices regarding font and margins, and that default
information may be added to information supplied by the user. As
it runs, a program also generates additional data to create the
desired final results.
Combining these ideas, processing is the term used when a com
puter follows programs in working with data. Thus, an application
that allows us to type and format documents is sometimes called a
wordprocessing program, because the application contains a range
of instructions to format our data as we designate.
Interestingly, over the years the distinction between a program
and application data has blurred somewhat. Often in early computer
work, special application data were written directly into a program. A
program was written specifically for a certain task. For example, the
act of processing text might have involved the use of only one type
font, and its details were an explicit part of the program. Further, the
length of a line on the page might have been specified as 80 charac
ters. Other type fonts and font sizes were not available, so there was
no need for a program to accommodate other possibilities.
However, as applications have evolved, they have become more
flexible. To accommodate various alternatives (for example, differ
ent type fonts), various details are now stored as data. Program
instructions continue to tell the computer what to do, but process
ing may be adjusted according to the data actually encountered.
Thus, in today's environment, a computer application includes both
the program(s) and the application data that it relies upon. When
such an application is purchased or installed, it typically contains
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