Information Technology Reference
In-Depth Information
As mentioned previously, an information system (IS) is a set of interrelated elements or
components that collect (input), manipulate (process), store, and disseminate (output) data
and information, and provide a corrective reaction (feedback mechanism) to meet an objec-
tive (see Figure 1.5). The feedback mechanism is the component that helps organizations
achieve their goals, such as increasing profits or improving customer service.
Feedback
Figure 1.5
The Components of an
Information System
Feedback is critical to the
successful operation of a system.
Input
Processing
Output
Input, Processing, Output, Feedback
Input
In information systems,
input
is the activity of gathering and capturing raw data. In pro-
ducing paychecks, for example, the number of hours every employee works must be collected
before paychecks can be calculated or printed. In a university grading system, instructors
must submit student grades before a summary of grades for the semester or quarter can be
compiled and sent to the students.
input
The activity of gathering and captur-
ing raw data.
Processing
In information systems,
processing
means converting or transforming data into useful out-
puts. Processing can involve making calculations, comparing data and taking alternative
actions, and storing data for future use. Processing data into useful information is critical in
business settings.
Processing can be done manually or with computer assistance. In a payroll application,
the number of hours each employee worked must be converted into net, or take-home, pay.
Other inputs often include employee ID number and department. The processing can first
involve multiplying the number of hours worked by the employee's hourly pay rate to get
gross pay. If weekly hours worked exceed 40, overtime pay might also be included. Then
deductions—for example, federal and state taxes, contributions to insurance or savings
plans—are subtracted from gross pay to get net pay.
After these calculations and comparisons are performed, the results are typically stored.
Storage
involves keeping data and information available for future use, including output,
discussed next.
processing
Converting or transforming data
into useful outputs.
Output
In information systems,
output
involves producing useful information, usually in the form
of documents and reports. Outputs can include paychecks for employees, reports for man-
agers, and information supplied to stockholders, banks, government agencies, and other
groups. In some cases, output from one system can become input for another. For example,
output from a system that processes sales orders can be used as input to a customer billing
system.
output
Production of useful information,
usually in the form of documents
and reports.
Feedback
In information systems,
feedback
is information from the system that is used to make changes
to input or processing activities. For example, errors or problems might make it necessary to
correct input data or change a process. Consider a payroll example. Perhaps the number of
hours an employee worked was entered as 400 instead of 40. Fortunately, most information
feedback
Output that is used to make changes
to input or processing activities.
