Evolution of Storage Disks Part III

A computer tape producing company by name Memorex (today a brand name of Imation), developed a read-write disk with a capacity of 175kB, and they called it as Memorex 650. This was fundamental for today’s hard disks; the Memorex 650 had tracks, sectors per tracks and some bytes per sector. This disk was out for the public in the year 1972.

As days passed on, in the year 1973 IBM released its first read write diskette. This new system was capable of storing 250¼kB of data. This new disk became very popular among the public and this disk format is known as Single Sided Single Density or SSSD format.

On the go, Burrough’s Corporation tried to develop a doubled sided 8-inch drive, with a capacity of 1MB. This storage capacity is 4 times bulkier than IBM’s SSSD. This disk provided enough room to run all softwares and store data. This diskette was produced in the year 1975, but was unpopular because of its poor quality.

Later in the year 1976, IBM released its Double Sided Single Density (DSSD) format disks with a storage capacity of 500KB and in the year 1977 IBM introduced a new format of disks known as Double Sided Double Density (DSDD) with a capacity of around 1-1.2 MB.