Information Technology Reference
In-Depth Information
alternatives may be found (e.g., inviting local speakers instead of
those requiring substantial travel costs), or dues might be raised.
Altogether, budgeting requires numbers (costs) to be arranged in
various categories, along with various computations (subtotals, to
tals, tax payments, tips, service fees) based on the items entered.
Such computationbased software is called a
spreadsheet
, and these
applications are sufficiently popular that many companies produce
spreadsheet software targeted at a wide range of users and applica
tions. As with databases, many computers are shipped initially with
some type of general spreadsheet package.
A computer also allows us to manipulate data and arrange it as
we'd like. In word processing, for example, computers allow you to
format text by changing margins, justifying lines, changing fonts,
and aligning equations. Each of these tasks involves the logical ma
nipulation of data. Spelling checkers also can review your text,
making use of a computer's ability to compare words with dictio
nary entries. Indeed, each word processing task can be described
carefully, completely, and precisely in logical terms. For example,
justifying a line involves adding spaces between words to make both
the left and right margins align properly. To perform this task, a
computer determines both how much space to add and where to
add it. Although this process requires some sophistication and sub
tlety to ensure that every page will look balanced and attractive, the
key point is that in order for the computer to complete the tasks, all
details are reduced to a basic list of rules. This helps the application
make good use of a computer's capabilities, and the computer can
thereby allow us to manipulate the data as we'd like.
A good application, like word processing or weather forecast
ing, solves a problem that requires the skills of a computer. Further,
the task that needs to be accomplished can be described fully; com
plete, unambiguous specifications can be written for the applica
tion. Also, given the specifications, detailed algorithms are available
