MEMORY

Primary Memory

- is directly connected to the central processing unit of the computer.

a. RAM – Random Access Memory

-RAM is memory that your computer uses to run programs and software applications on your computer. Without RAM your computer won't function. The more RAM you have the faster and more smoothly your computer will run.

-ROM (read-only memory) is nonvolatile memory

-ROM is used extensively to program operation of computers, as well as in devices like cameras and controls for the fuel injectors in modern cars. However, ROM plays a limited role in the PC (personal computer).

b. ROM – Read Only Memory

ROM (read-only memory) is a type of memory that stores data even when the main computer power is off. This is necessary so that the system can access the data it needs to start up. When stored in ROM, information that is required to start and run the computer cannot be lost or changed.

Secondary Memory

-Requires the computer to use its input/output channels to access the information, and is used for long-term storage of persistent information.

a. Magnetic disk/storage

b. Optical disk

-Optical disc storage is non-volatile and sequential access

The following forms are currently in common use:

* CD, CD-ROM, DVD: Read only storage, used for mass distribution of digital information (music, video, computer programs)

* CD-R, DVD-R, DVD+R: Write once storage, used for tertiary and off-line storage

* CD-RW, DVD-RW, DVD+RW, DVD-RAM: Slow write, fast read storage, used for tertiary and off-line storage