EPROM stands for Erasable Programmable Read-Only Memory. It is a type of non-volatile memory chip that functions similarly to standard ROM in that it retains data without power, but offers the distinct flexibility of being re-writable.

Unlike modern Flash memory, erasing an EPROM is a physical procedure rather than a software command. These chips are characterized by a small, transparent quartz window on their top surface. To reset the memory, the chip must be removed from the circuit and exposed to strong ultraviolet (UV) light through this window. This clears the stored data, allowing the chip to be reprogrammed with new code or samples using a dedicated device called an EPROM programmer. This technology was crucial in early digital audio gear for storing operating systems and sound banks.