Some would say Input, Processing, Output. The diagram would be an arrow from input to processing, then an arrow from processing to to output. Then an arrow from output to Input in this way of looking at it. You will find more complicated descriptions and diagrams, too.
The data processing cycle:
It is Sequence of steps performed repeatedly by a computer in the execution of a program. The computer's central processing unit (CPU) continuously works through a loop. It fetches a program instruction from memory. Then the CPU fetches any data it needs. Then it applies the data to the program. It stores the result in memory. Then it fetches another program instruction.
Others include more stages: http://www.enterprisefeatures.com/6-important-stages-in-the-data-processing-cycle/