A processor is a person or machine that goes through certain procedures to achieve a particular result. A milk processor milks cows, stores the milk, pasteurizes it, and bottles it before you buy it a store.
There are many different kinds of processors, but what they all have in common is going through a process, a series of specific steps, to accomplish something. The food processor in your kitchen quickly dices pounds of onions, a task that would take considerable work to complete by hand. A word processor does the same for writing, allowing you to easily edit text. Computer processors control and move vast amounts of data. The Latin root means "advance or progress."