Sequential File Processing

Sequential file processing is an instance of the "push the stuff through the tool" model. This is how data processing was done when the data files were stored on sequential media such as punched-card decks and magnetic-tape reels, and the processing hardware was weak.

The figure shows a billing application . The input files (on the left) are the raw material, the computer (in the middle) is the tool, and the output files (on the right) are the products. The computer does not need to be powerful because it is processing one input record at a time.

This early fact of technological and economic life, that media were sequential, the processing machinery was weak, and files were large, led us to think of all automated information processes as sequential file processes.