Hardisk

 As floppy disks, hard drives also store data in the form of tracks, sectors, and clusters. Sector recorded the computer operating system based on its cluster. Windows operating system provides a unique number to each cluster and record address of the file on your hard drive using the virtual file allocation table (VFAT, Virtual File Allocation Table). VFAT is one method to save and find files based on the cluster address is used. Therefore, VFAT contain every value in every cluster that describes the location of the disk where the cluster is located. Sometimes the operating system considers a cluster as a cluster that is being used, although at that cluster does not contain any files. This is called a lost cluster, and users can liberate these clusters (which means you can add disk space) using ScanDisk utility in Windows.
C.1. Nonremovable hard drive (HDD Internal)
Internal nonremovable hard drive is hard to remain in the unit and the computer system used to store almost all programs and most of the data file. Notebook type consists of several metal or glass plate (glass) 1 to 5.25 inch in diameter (generally 3.5 inches), arranged in the form of coils and contains data on both sides piringannya. Read / write head located on each side of the disc, arranged by the activator arm that moves back and forth to find the exact location on the disc. All these components are protected in anti-air packaging that can be free from impurities such dust.
Nonremovable hard drive capacity varies between 40 to 300 gigabytes. There's even a hard drive terabyte unit has reached the equivalent of thousands of gigabytes. One gigabyte is roughly equivalent to writing all the 20,000 pages, while video and sound files are usually size 10 megabytes or more.
Disk rotation is much faster than disk, so the data / programs on the hard drive can be accessed faster. The speed of the hard disk expressed with units of revolutions per second (rpm), which ranges from 5400 to 7200 rpm. Disk rotation speed only 360 rpm, while the hard drive at 7200 rpm (roughly equivalent to the speed of 300 miles per hour).
C.2. Portable Hard Drive (HDD External and Removable)
There are two types of portable hard drives, among others:

    * External hard drives, external hard drive is a hard drive that can be placed outside the unit remains berpembungkus system and anti-air. Through cable, hard drive connected to the computer system unit to the FireWire port, USB or other ports. Minimum capacity of 250 gigabytes.
Removable hard drive, removable hard drive or hard-drive cartridge consists of one or two discs equipped with head read / writes, protected in rigid packaging and can be inserted into the cartridge drive unit of microcomputer systems. Catridge, with a capacity of 80 gigabytes or more, usually used for backups and move data files are large, such as a spreadsheet file or desktop-publishing-sized