1. PROM:
PROM stands for Programmable Read Only Memory and is initially blank. The manufacturer can write data/program on it by using special devices. However, once the program or data is written in PROM chip, it cannot be changed.
2. EPROM:
EPROM stands for Erasable Programmable Read Only Memory and is also initially blank. Unlike PROM, the data written in EPROM chip can be erased by using special devices and ultraviolet rays.
3. EEPROM:
EEPROM stands for Electrically Erasable Programmable Read Only Memory. This kind of ROM can be written or changed with the help of electrical devices. So data stored in this type of ROM chip can be easily modified.
