Is the operating system installed on the ROM of the ARM device?

Question

Is the operating system installed on the ROM of the ARM device (when changing OS in the smartphone, I find the term “changing the ROM” being used)?

Answer 1

The term "ROM" used by mobile maniacs is not the OS. ROM's are changing for different appearance as well as user interface. The OS will be remaining the same even after flashing different ROM. There are two types of ROM

• Stock ROM - The ROM comes along with the phone
• Custom ROM - Created by different developers customizing existing ROM.

However changing ROMs needs root privilege. Your phone need to be rooted before changing ROM

Eg for Custom ROMs : CyanogenMod, Hyperion, Jellyblast etc

Eg for OS : Gingerbread, Jellybean, Kitkat (upcoming)

Answer 2

When it comes to computing, a ROM can mean 2 different things.

Generally, ROM is an area of Read Only Memory. This is generally the the firmware of the device, basic information that should not be changed and is generally vital to the basic input and output systems of the device.

When it comes to Android Devices, a ROM has come to be an image of an operating system that can be placed on the device, a better term, would be a system image.

Android ROMs got this name because they in part, take from the first. Android devices have onboard memory that is partitioned in 2, one for the OS, and one for the User Data, the OS portion, being the part that you overwrite with a ROM, is ReadOnly.

To answer the question, the operating system is not installed on a ROM, it is however installed on a Read Only partition of the device which can be modified using root.

Answer 3

ROM is a misnomer here - since it means read only memory, and you can overwrite the OS on a phone - for example when you install something that the phone didn't come with.

The phone's OS is really stored on flash memory (which practically is writable solid state memory, and neither a proper fixed rom, or a erasable read only memory chip). Phone OSes are not stored on roms at all.