Computers before Windows

HARDWARE
What is RAM?
RAM (ram) stands for random access memory. RAM is the computer's workplace for holding programs and the results of programs. Almost all of the instructions to make the computer do any of the things it can do, must be loaded into RAM for the computer to work. RAM starts out with very few instructions in it when the computer is first turned on, but fills up with the programs that you load into it, to do the work and the results of any previous work. In general, the more RAM a computer has, the more data it can work with at one time. Adding more RAM generally allows the computer to work more complex problems because the software necessary to complete complicated tasks take up more RAM space than more simple programs. RAM is measured in bytes. One byte could represent the letter "a" , the number "I", or an instruction for the computer. Approximately 1,000 bytes (bites) is called a kilobyte (kill-o-bite). Approximately 1,000 kilobytes is called a megabyte (meg-a-bite). Most computers today have between 256 and 640 kilobytes of RAM. Most computers can be expanded to several megabytes of RAM.

What is ROM?
ROM (rom) stands for read only memory. ROM holds some of the instructions that the computer uses for starting itself and operating some of its hardware, like the serial and parallel port. The ROM of a computer is used by the operating system to talk to other types of devices, like the disk drive and monitor.