RAM and ROM

RAM and ROM

1. rom

   • ROM is memory that cannot be changed by a program or user. ROM retains its memory even after the computer is turned off. For example, ROM stores the instructions for the computer to start up when it is turned on again.
   • ROM stores the program required to initially boot the computer. It only allows reading
     • Short for Read-Only Memory, ROM is a type of "built-in" memory that is used with computers and other electronic devices. As the name indicates, data stored in ROM may only be read; it is either modified with extreme difficulty or not at all. ROM is mostly used for firmware updates. A simple example of ROM is the cartridge used with video game consoles; which allows one system to run multiple games. Another example of ROM is EEPROM, which is a programmable ROM used for the computer BIOS, as shown in the picture.

2. ram

   • RAM is a fast temporary type of memory in which programs, applications and data are stored.
   • If a computer loses power, all data stored in its RAM is lost.
     • Dynamic RAM is the most common type of memory in use today. Inside a dynamic RAM chip, each memory cell holds one bit of information and is made up of two parts: a transistor and a capacitor. These are, of course, extremely small transistors and capacitors so that millions of them can fit on a single memory chip. The capacitor holds the bit of information -- a 0 or a 1 (see How Bits and Bytes Work for information on bits). The transistor acts as a switch that lets the control circuitry on the memory chip read the capacitor or change its state.

3. volatile memory

   • Volatile memory is a type of storage whose contents are erased when the system's power is turned off or interrupted. For example, RAM is volatile; meaning users will lose a document if they do not save their work to a non-volatile classification of memory, such as a hard drive, before shutting down the computer.