Computer parts - Hard Drive

Hard disk is permanent data storage media, so data is not lost even if power is switched off. Hard drives contain magnetic disk capable of storing data. The size of hard disk expressed in Byte (B), for example: 160GB (160 billion bytes). Harddisk was first discovered by Reynold Johnson in 1956. The first hard drive size 4.4 MB.
Parts of the hard drive

Parts of the hard drive

Part of Hard Disk

1. Spindle

Harddisk composed of spindle rotation at the center of the pieces of magnetic disk data storage. Spindle is spinning rapidly, therefore it must use high quality bearings.

Formerly hard drive using the ball bearings but now the hard drive is using a fluid bearing. With the fluid bearing friction and noise level can be minimized. Spindle is a decisive round of the hard disk. The faster the spin the faster rpm hard drive data transfer.

2. Magnetic disks (Magnetic Disk)

In this magnetic disk data storage performed on the disk. The disc-shaped magnetic thin plate with a shape such as a CD-R. In the disk there are some magnetic discs.

Harddisk who first made, consisting of 50 dish size magnetic disk 0.6 meters and rotates with the speed of 1200 rpm. Currently disk rotation speed has reached 10.000rpm to achieve 3.0 Gbps data transfer.

3. Read-write head

Read-write head is the maker of data from magnetic disks. Head is floating a short distance with a thin magnetic disc. Formerly head in direct contact with the magnetic discs causing wear on the surface because of friction. Now between the head and the magnetic discs already are spaced so that the hard drive longer life.

Read-write head is made of materials had been developed, ranging from Ferrite head, MIG (Metal-In-Gap) head, TF (Thin Film) Head, (Anisotropic) Magnetoresistive (MR / AMR) Heads, GMR (Giant Magnetoresistive) Heads and now used are CMR (Colossal Magnetoresistive) Heads.

4. Enclosure

Enclosure is the outer layer wrapping the hard disk. Enclosure serves to protect all parts of the hard drive so as not exposed to dust, moisture and other things that can cause data loss.

In the enclosure there is breath filter which makes hard drives are not airtight, it aims to remove the heat that is inside the hard drive because the process of spindle rotation and the reading of the Read-write head.

5. Interfacing Module

Interfacing module is a set of electronic circuit that controls the inner workings of the hard disk, process the data from the head and produce data that is ready to be read by the next process. Interfacing the first module is a system widely used IDE (Integrated Drive Electronics) with a system that has ATA 40-pin connection.

The newest technology is the technology of interfacing module Serial ATA (SATA). With the single SATA hard disk is handled by a separate bus inside the chipset, so the handling is faster and efficient. SATA hard drives are now gradually replacing the old ATA hard drive began to disappear from the market.

Hard Drive Data Unit

Unit disk data expressed in Byte (B) and units of data transfer disk expressed in bits (b). Now that 500GB hard drive size has reached even 1000 GB (1 Terra Byte), so that storing data become more liberal.

Why the property is not the same size hard drive hard drive capacity?

Please note that 1 KB = 1024 B 1000B so it is not, so 1GB is not 1.000.000.000B but 1.073.741.824B.

Some well-known hard drive manufacturer

1. Seagate
2. Maxtor
3. West Digital
4. Quantum
5. Samsung

Drive Technology

1. RAID (Redundancy Array of Independent Disks)

RAID is a technology combining several hard disk by a computer operating system is considered to be one hard drive. This concept was first defined by David A. Patterson, Garth A. Gibson and Randy Katz at the University of California, Berkeley in 1987.

The advantage is increased speed RAID disk access. By replacing a large disk with a few small hard drive it is possible to read data in parallel on each disk. Diibatatkan RAID disk that produces a database of data in parallel in accordance with index addressing the hard disk.

2. SMART (Self Monitoring, Analysis and Reporting Technology)

SMART is disk performance monitoring technology. With the SMART hard drive detects an error and report this error to the system. SMART paertama times spearheaded by Compaq, but now almost all uses SMART technology.

The advantages of using SMART is the presence of an early warning of abnormalities that occurred on the disk so that users can perform preventive measures such as back-up data.