RAMAC may refer to: IBM 305 RAMAC, a computing system introduced in 1956 IBM 350 RAMAC, a disk storage unit introduced in 1956 as a bundled component of the IBM 305 RAMAC IBM 650 RAMAC, a computing system consisting of an IBM 650 with an IBM 355 Disk Storage unit and introduced in 1956 IBM 9394 RAMAC Array, a disk storage array and controller unit introduced in 1994 which uses data striping