Background processing can be best defined by its action. It simply performs tasks in the background of a computer while a computer user performs actions in the foreground of the computer. For example, in background processing, a computer user can actively manipulate one application using a keyboard and a computer screen while separate operations are performed at the same time and in the background. In many cases, background processes work completely autonomously and the user isn't even aware that the processes are being performed.
Processing data in the background of any computer is an integral part of the functioning of a computer. Backgrounds can be high-priority, same-level priority or low-level priority compared to the application that a user is working with on-screen. As long as background processing is achieved within an acceptable time frame and doesn't interfere with the activities of the user or the overall functioning of the computer, it can be considered to be successful.
One popular example of background processing involves the common printer. When a computer user works on a word processor to type up a document, saves it and commands the computer to print it, the command is transferred over to the printer by way of the computer's background processes. This activity takes place independent of whatever is happening on the computer user's screen. In fact, a computer user can continue to make modifications to the document, open and type a new document or work in an entirely new application altogether while the computer is engaged in background processing.
The lack of interaction between computer user and background processes should not be misunderstood to mean that the processes are unimportant. There are certain background processes that are just as important as those applications that are being interacted with in the foreground. Some computers have the ability to prioritize tasks and regulate how much energy is devoted to each. Generally, though, a background process is relatively low priority and has minimal output.
Background processes can be usually categorized as being either a daemon or a compute-intensive task. The average computer user will be more familiar with the work of daemons, as they help take care of common functions like email transferring, web page serving and time synchronization. Their interactions are not with users, but with programs or other computers on a network. They use very little memory and don't put a large dent in CPU usage, so computer users may work on a machine for years without realizing that these processes exist and are actually taking place while they are concentrating on a task in the computer's foreground.