Why is it called Read Only Memory?

[Mr Robot]

I was in my computing class yesterday and my teacher was talking about how you can only read to ROMs as they are read only memory and i raised the question "to read an OS or pictures from a drive you first have to write to it e.g. if your building a pc you have write to it in order to load the OS onto it" if this is true why is it called Read Only Memory?

 

Many Thanks, Mr Robot

[Electronics Wizardy]

once you write it you cant change it.  so memory like eeprom can only be wiped and re written. you cant just change some data like you can on hdd or flash

[Sauron]

ROM strictly indicates read only memory. Of course data must have been written to it the first time, but in this case it means that it's only written to once and the user doesn't have the capability or permission to write to it again. For all intents and purposes, it cannot be written to by you so you should consider it as read only.

[Mr Robot]

Ohh my mistake i thought roms where storage devices but am i right in saying they are what hold the system bios?

[tlink]

because if it can't hold data it wouldn't be memory, and to hold data you would first have to store it. its called read only because the initially stored data can only be read and not overwritten.

[SpaceNugget]

A hard drive is not ROM. I think that is your main issue in understanding. Your OS and pictures are not in ROM, they are in a drive.

[Mr Robot]

ok thanks that was were i was confused because my teacher said an example of ROM is a hard drive or ssd @WaxyMaxy

[bgibbz]

9 minutes ago, Mr Robot said:

Ohh my mistake i thought roms where storage devices but am i right in saying they are what hold the system bios?

Bios is stored on eeprom, of electrically erasable programmable read only memory. Essentially it's read only memory that can be erased and re written for something like a bios update. 

 

 

An example of a rom is a DVD rom, once written they are unable to be rewritten without specialty designed disks

[Electronics Wizardy]

9 minutes ago, Mr Robot said:

Ohh my mistake i thought roms where storage devices but am i right in saying they are what hold the system bios?

The os was stored on rom in the old days and on many embedded systems

[Mr Robot]

ok