gigabyte

gigatavu puhekieltä 109, one billion (1,000,000,000) bytes. SI symbol: GB
1981, IBM, http://bitsavers.informatik.uni-stuttgart.de/pdf/ibm/dasd/GA26-1664-1_3380_IBM_3380_Direct_Access_Storage_Description_and_Users_Guide_Dec81.pdf IBM 3380 Direct Access Storage Description and Users Guide'', page 1

The IBM 3380 Direct Access Storage is a disk storage device with a storage capacity of 2.5 gigabytes (billion bytes) per unit, an increase of almost four times the capacity of the IBM 3350 Direct Access Storage.