Over the years there have been major improvements in the areas of areal density, capacity and performance. It was IBM again who in 1961 invented the first disk drive with air bearing heads, followed by the removable disk drive in 1963 and the eight-inch floppy in 1970.
In 1973, they came up with the IBM 3340 "Winchester" disk drive, the technology on which all the modern disk drives of today are based. Named after the Winchester 30-30 rifle, it is the first prominent use of Low Mass and low load heads with lubricated media. This was the first instance of having two spindles for data storage capacity of either 35MB or 70MB.
1980 saw the launch of the world's first gigabyte-capacity disk drive, the IBM 3380, which was the size of a refrigerator, weighed 550 pounds and had a price tag of US$40 000. The SCSI standard was released six years later.
In 1986 the 16-bit parallel interface was introduced, the ATA interface, which has undergone so many changes since its introduction, to improve the speed and to reduce the size. It is also known as IDE, Parallel ATA, PATA and ATAPI (Advanced Technology Attachment Packet Interface). The last version of ATA (ATA-7) was introduced in 2001, supporting data transfer at 133MB/sec.
In 1991 the 2.5-inch hard drive was introduced with 100MB capacity. The first 1.3-inch hard drive, the HP C3013A came in 1992, followed by release of the Micro drive with 170MB and 340MB capacities by IBM.
The introduction of Serial-ATA (SATA) in 2003 was a breakthrough in hard drive technology. 2005 witnessed so many developments, like the shipping of the first 500GB hard drive and standardization of SATA 3G. In the same year, Seagate introduced Tunnel Magneto Resistive Read Sensor (TMR), Thermal Spacing Control, a faster SAS and Perpendicular recording in consumer HDDs by Toshiba. Seagate introduced the first 750GB hard drive and Toshiba launched the first 200GB 2.5" hard drive utilizing Perpendicular recording in 2006.
Anatomy of the Common Hard Drive
All hard drives have a basic structure and are made up of almost the same equipment. The basic parts of a hard drive are the platters, spindle and spindles motors, the read and write heads and the head actuators.
Platters are nothing but the glass or ceramic disk present inside the drive where all the data is stored magnetically. Data transfers from the read/write heads to the magnetic layers of the platters, and it is then stored on the tiny domains of the positive and negative magnetization on both the sides of the platters. The platters are separated by disk spacers and fixed to the rotating spindle that is powered by the spindle motor and used to spin the platter at a predetermined constant rate. The read/write heads read and write data to the platters and they move around the platters with the help of a head actuator arm. The combined performance of these parts together greatly contributes to the overall performance of a hard drive.
The platters, spindle, spindle motor, head actuator and the read/write heads are present in a chamber called the head disk assembly (HDA).