Multitasking for Not Yet Techies

Multitasking has become somewhat of a metaphor for how many of us live our lives in this complicated age. Certainly I often "multitask" in the sense that I'll my computer downloading a file off the Internet, my washing machine cleaning a load of clothes, my frying pan cooking up some eggs -- all while I'm eating a dinner. However, most of what we call computer multitasking is simulated.

True multitasking would be a CPU doing more than one task at a time - in reality, one CPU can do just one thing at a time. The trick is, it can juggle a number of different chores, racing back and forth between them so fast that you think it is crunching those spreadsheet numbers while printing up your novel.

This type of multitasking is accomplishing through time slicing, which divides CPU computing cycles (which can be hundreds to millions cycles per second) between multiple tasks. While the CPU bounces back and forth between applications many times a second, you think it's doing two things at once.

Preemptive -- The operating system controls how long the CPU works on each task. It forces applications to share the CPU.

Cooperative -- Once a CPU begins a process, the operating system cannot stop it. It's like a child who refuses to share his cake with his brother.

High performance multitasking network operating systems must use preemptive, or computer resources will not be used and shared fairly.

Next: Neural networks