ROM (Read-Only Memory) is non-volatile memory that keeps its contents when the power is off. It is traditionally written at manufacture or very rarely changed, and holds the code a device needs to start up.
Why it matters
Every device needs some permanent instructions to begin booting before storage is available. Those live in ROM or in flash memory that behaves like it. Modern devices usually use rewritable flash, which allows firmware updates.
The name is mostly historical. Types include mask ROM, PROM, EPROM and EEPROM.
Example
When you press the power button, the processor starts by running code from a ROM or flash chip:
power on -> boot code in ROM/flash -> firmware init -> bootloader -> operating systemIf that chip is corrupted, the device may not start at all, often called being bricked.
Common misconceptions
- ROM can never be changed. Flash and EEPROM variants are updated through firmware flashing.
- ROM is the same as storage. It is a tiny amount of boot code, not your files.
- Phone ROM means the whole system image. In custom firmware communities the term is used loosely.
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यह पेज सामान्य जानकारी है, जिसे हमारी संपादकीय टीम ने लिखा है और दस्तावेज़ीकरण बदलने पर अपडेट किया जाता है। सर्वर और प्रदाता अलग-अलग होते हैं, इसलिए बदलाव पहले सुरक्षित तरीके से जाँचें। देखें: संपादकीय नीति और अस्वीकरण.