A data processing normally consists of a number of basic processing operations performed in some order.
First step involved in data processing is the recording. Recording basically means transferring of data onto some form of document. It occurs not only during the origination step and during the distribution step but throughout the processing cycle, for example recording of the final results.
Second step involved is the duplicating of data. During this process same data is reproduced into different forms. This process consists in reproducing the data onto many documents. Duplicating may be done while the data are being recorded manually, or it may be done afterwards by some machine. Before computers were invented data was duplicated by recording a report by typing it at the same time duplicating it by using a carbon paper.
Third step involved is validation of the data. Since recording is usually done by manual means it is important that recorded data be carefully checked for any errors or omissions. One example of verification is that the punched cards and typed reports are reread for correctness.
Fourth step involved is the validation. This operation separates data into various categories and classifying can usually be done in more than one way. For example, a set of student questionnaires may be classified according to the student’s sex or according to the student’s year at school or their grades.
Sorting is the fifth step in data processing operation. Data needs to be arranged in specific order and this operation is called sorting. Examples of sorting are names in a telephone directory in alphabetical order; employee records may be sorted according to employee ID card number. In these cases unclassified data are sorted. Sorting may also take place after classifying.
Sixth operation is the merging. In merging two or more documents or set of data is combined to form a single document. Before merging data all sets having been sorted by the same key and puts them together to form a single set of data. In other words in this step two files of the same type are combined to form the third file.
The seventh and the last step is the calculation. In this step certain calculations are performed on the original data. This step is done on numeric data.