Memory

The processor is the brain of the computer. All fundamental computing takes place in the processor. Other components contribute to the computation by doing such things as moving data into and out of the processor. But the processor is where the fundamental action takes place.

Unlike a human brain, which combines memory with processing power, a computer processor has very little memory. It must rely on other components to hold data and programs and to save results. The memory in a computer system is of two fundamental types:

• Main memory:
  • closely connected to the processor.
  • contents are quickly and easily changed.
  • holds the programs and data that the processor is actively working with.
  • interacts with the processor millions of times per second.

• Secondary memory:
  • connected to main memory through the bus and a controller.
  • the contents are easily changed, but changes are slow compared to main memory.
  • used for long-term storage of programs and data.
  • before its data and programs can be used, they must be copied into main memory.