Explain the Programmable ROM (PROM) - Computer Memory?

This is a kind of ROM that can be programmed using special equipment it can be written to, but only once and this is useful for companies that make their own ROMs from software they write, since when they change their code they can create new PROMs without requiring expensive equipment. This is alike to the way a CD-ROM recorder works by letting you "burn" programs onto blanks once and then letting you read from them many times. Indeed, programming a PROM is as well called burning, identical to burning a CD-R, and it is comparable in terms of its flexibility.