ROM it is a computer term that means Read Only Memory ("Memory of only reading" ). It's about a storage medium that use the computers and other electronic equipment.
The data stored in the ROM cannot be modified by the common user. This type of memory It is used to store the firmware (software linked to specific hardware) and other data essential for the operation of the computer.
There are various kinds of ROM. The oldest are the MROM (which store data permanent and unmodifiable), while other more modern are the EPROM and the EEPROM flash , which can be rewritten and programmed.
The first computers had their OS stored in ROM. For updates, it was necessary to replace the ROM chip with a new one. Technology has advanced considerably since then and in today's computers only a few programs are hosted on ROM, while most are on hard drives or Flash memory, among other technologies.
It should be noted that certain video game consoles use ROM memories in cartridges , as is the case with games Sega Mega Drive , Super nintendo or Game boy , for example. The ROM only works when the cartridge is inserted into the corresponding space and proceeds to the reading of the data. When you remove the cartridge, the information is no longer accessible.
In the case of computers, ROM is still used to store data since they offer higher speeds than hard drives. On the other hand, it is impossible to read a program that requires the execution of a disk from the disk itself and this is one of the reasons why the BIOS of the computers are hosted in the ROM.
Differences with RAM
Already from the nomenclature, there are clear differences between ROM (Read Only) and RAM (Random Access). RAM is better known by users, since it is usually part of the technical specifications of computers, video game consoles, mobile phones and tablet PCs, among others dispositives, and is usually associated with the power of the team, although this is not correct.
The meaning of the word "random" in the name of the RAM refers to the fact that each time it is used, the data is stored in random cells, and the access time to each of them does not depend on its location. physical level inside the card since, unlike a hard disk, instead of crossing it until it reaches the desired point it is addressed as if it were a Cartesian table.
RAM, which is also known as temporary or volatile, presents the possibility of being rewritten and read constantly; in fact, it is one of its essential benefits, the task for which it was created. In it the programs that the user wishes to execute, including the operating system itself, trying not to allocate the same space to two applications simultaneously.
A characteristic that can be considered as a weak point is that when the power supply is cut, its content disappears. Hence the need to have a permanent storage medium, where applications and personal documents can be stored. The ROM was one of the answers to these requirements, and was designed in such a way that it had enough information for the device to start up, control the connected devices and components, load and execute the operating system and other functions. , which make up the so-called BIOS.
Taking into account all the features just mentioned and adding them to the inability to write freely in ROM, it is clear that although their names differ only in one letter, RAM and ROM technologies assume very different roles.