Regardless of the application, most computers operate in the same fashion. We’ll defer the discussion of this until a little later.
Regardless of the mechanism, processing is the act of performing calculations, perhaps massively. The calculations are performed according to the specification of a program. As a result of the calculations, a computer either produces/stores information or a decision to act.
A traditional data processing system produces/stores information that will be read and interpreted by humans. For example, a Franchise Tax Board system accumulates all the recorded income of individuals and compute the annual tax owed by taxpayers. A Department of Motorized Vehicles system records the history of a vehicle and compute the proper amount of vehicle tax.
An embedded system, on the other hand, does not produce information. Instead, it make decisions and perform actions as a result. For example, a thermostat makes a decision of whether the furnace and blower should be turned on or off. An antilock brake controller makes a decision of whether to tighten or release a brake caliper.
The specification of processing is called a program or a script.