NOR (non-volatile read-only memory) flash is a type of non-volatile memory used in embedded systems. It uses floating gate transistors to store data in a cell. It is typically used as a bootstrap or starter code in programmable devices such as microcontrollers or FPGAs. NOR flash can be read, written and erased, allowing it to store code and data. It is typically more reliable than other non-volatile storage methods, such as EPROM or EEPROM. It is also more cost-effective than RAM memory and is often the primary form of storage used in low-cost electronic devices.