THE THREE STAGES OF DATA PROCESSING
Data processing can be likened to the manufacturing process. In manufacturing,
raw materials are processed, or made into a finished product. The raw materials may
be considered "input" to the processing machine. The finished product is "output." In
the electronic computer, data are the raw material or input to the computer. The
finished product, or output, is usually a printed report or an updated file containing data
that have been processed or manipulated in some way. The three functions (or stages)
of data processing are: input, process (or manipulation), and output. Input involves
capturing data and getting it into a farm understandable to the computer. Processing
encompasses the various steps taken by the computer to manipulate the data and
provide information. Output makes the computed results of processing available for use
Figure 3-1. Data processing compared to manufacturing.
Three steps are involved when inputting data into the computer: collection,
verification, and coding. Collection refers to gathering the data from a variety of sources
and assembling it. Verification means checking the data to determine whether it is
accurate and complete, and if it should be included for processing. Coding is translating
the data into machine-readable form. Data punched into IBM cards is one example of
During processing or manipulation, one or more of the following tasks may be
performed on the input data.
a. Classifying. Data are organized by characteristics meaningful to the user.
For example, a student may be identified by Social Security number, class and exam