What Does Non-Volatile Memory Mean?
Non-volatile memory (NVM) is a type of computer memory that has the capability to hold saved data even if the power is turned off. Unlike volatile memory, NVM does not require its memory data to be periodically refreshed. It is commonly used for secondary storage or long-term consistent storage.
Non-volatile memory is highly popular among digital media; it is widely used in memory chips for USB memory sticks and digital cameras. Non-volatile memory eradicates the need for relatively slow types of secondary storage systems, including hard disks.
Non-volatile memory is also known as non-volatile storage.
Techopedia Explains Non-Volatile Memory
Non-volatile data storage can be classified into two types:
- Mechanically addressed systems
- Electrically addressed systems
Mechanically addressed systems make use of a contact structure to write and read on a selected storage medium. The amount of data stored this way is much larger than what’s possible in electrically addressed systems. A few examples of mechanically addressed systems are optical disks, hard disks, holographic memory and magnetic tapes.
Electrically addressed systems are categorized based on the write mechanism. They are costly but faster than mechanically addressed systems, which are affordable but slow. A few examples of electrically addressed systems are flash memory, FRAM and MRAM.
Some examples of NVM include:
- All types of read-only memory
- Flash memory
- Most of the magnetic storage devices, such as hard disks, magnetic tape and floppy disks
- Earlier computer storage solutions, including punched cards and paper tape
- Optical disks