What is the difference between RAM and ROM?

RAM (Random Access Memory) and ROM (Read-Only Memory) are both types of computer memory, but they serve opposite purposes.

RAM (Random Access Memory)

• Volatile — loses its contents when power is cut
• Read and write — the system constantly changes what's stored
• Holds actively running programs, open files, and temporary data
• Faster, but more expensive per gigabyte than storage drives

ROM (Read-Only Memory)

• Non-volatile — keeps its contents without power
• Traditionally read-only, though modern variants (like EEPROM and flash) can be rewritten in controlled ways
• Stores firmware — the low-level startup instructions a device needs before an operating system even loads

A simple way to remember it: RAM is your desk while you're working — fast to reach, but cleared at the end of the day. ROM is more like a permanently engraved instruction manual the device consults to know how to start up in the first place.