ROM (Read Only Memory) would play an important role in making computers easier to use. Unlike RAM (Random access memory) ROM would not lose it's contents when the power was turned off. Early microcomputers lacked ROM memory and had to be started by entering a bootstrap program, or sometimes the whole program that the user would want to run, directly into the computers memory via switchs on the front panel. ROMs enabled computers to "autostart". The EPROM (Erasable Programable Read Only Memory) would allow designers to program ROMs themselves and even erase them by exposing them to ultravoilet light (this is why EPROMs have a clear window on top). The photo shows the first commercially available EPROM, the 1702A, made by Intel. It featured 256 Bytes of storage and could be erased and reprogramed hundreds of times.