Computer BIOS

The oldest ROM-type storage media can be dated back to with drum memory. Today, ROM-type storage media is still used and continues to be improved upon for better performance and storage capacity.

Programmable ROM

Alternatively referred to as a FPROM (field programmable read-only memory) or OTP (one-time programmable) chip, PROM or Programmable ROM is short for Programmable Read Only Memory and is a computer memory chip first developed by Went Tsing Chow in  that is capable of being programmed once after it has been created. Once the PROM has been programmed, the information written is permanent and cannot be erased or deleted. A good example of a PROM in a computer is the in early computers.

EPROM

Short for Erasable Programmable Read-Only Memory, EPROM is a memory chip that was invented by in while at that can only be read. If exposed to ultraviolet light an EPROM can be reprogrammed if needed, but otherwise does not accept or save any new data. Hardware manufacturers use EPROM when it may be needed that the data contained on the EPROM needs to be changed. An EPROM chip is distinguishable by a small quartz crystal (not glass) circle window that exposes the chip so that can be reprogrammed. In the picture shown on this page is an example of an 8048 made by and is an example of an EPROM chip.

EEPROM

Short for Electrically Erasable Programmable Read-Only Memory, EEPROM is a can be erased and reprogrammed using an electrical charge that was developed by while at in like most memory inside a computer, this memory remembers data when the power is turned off.

EEPROM was a replacement for and chips and is used for later computer's that were built after. Having a computer with an EEPROM allows a computer user to in their computer without having to open the computer or remove any chips.

can take the normal example of EEPROM is the pen drive…

 The Advantage of  ROM are.

• they are non-volatile
• they are cheaper than RAM
• they are static and do not refreshing
• they are more reliable than RAM as their circuit is simple
• they are available in longer sizes the RAM.
• They are easier to interface than RAM.