A good answer might be:

The addition took place in the processor of the computer.

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 in and out of the processor), but the processor is where the fundamental action takes place.

Unlike the 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.
  • Very closely connected to the processor.
  • Used to hold the programs and data that the processor is actively working with.
  • The processor interacts with it millions of times per second.
  • The contents of main memory is easily changed.
  • Not used for long-term storage.
  • Low capacity compared to secondary memory, but access is fast.

• Secondary memory.
  • Connected to main memory.
  • Used to hold programs and data.
  • The processor does not interact directly with secondary memory.
  • When programs and data become active, they are copied from secondary memory into main memory where the processor can interact with them.
    • A copy remains in secondary memory
  • The contents of secondary storage is easily changed.
  • Used for long term storage.
  • Huge capacity compared to main memory, but access is slow.
  • Usually data and programs are organized into files in secondary memory.

Main memory is where programs and data are kept when the processor is actively using them. Main memory is intimately connected to the processor, so moving instructions from the program and data into and out of of processor is very fast. Main memory is sometimes called RAM. RAM stands for "Random Access Memory" which means that the memory cells can be accessed in any order.

When people say that a computer has "32 megabytes of RAM" they are talking about how big its main memory is. (There will be more about bytes and megabytes later on in these notes.) Nothing permanent is kept in main memory. Sometimes things are placed in main memory for just a few seconds; only as long as they are needed.

QUESTION 4:

Say that you are using a word processor program to write a letter.

• Where (in the computer system) is the program you are running?
• Where are the characters you have typed?