tailieunhanh - Types of Storage Devices

Storage devices hold data, even when the computer is turned off. The physical material that actually holds data is called a storage medium. The surface of a floppy disk is a storage medium. The hardware that writes data to or reads data from a storage medium is called a storage device. A floppy disk drive is a storage device. The two primary storage technologies are magnetic and optical. | Types of Storage Devices lesson 9 This lesson includes the following sections: Categorizing Storage Devices Magnetic Storage Devices Optical Storage Devices Categorizing Storage Devices Storage devices hold data, even when the computer is turned off. The physical material that actually holds data is called a storage medium. The surface of a floppy disk is a storage medium. The hardware that writes data to or reads data from a storage medium is called a storage device. A floppy disk drive is a storage device. The two primary storage technologies are magnetic and optical. The primary types of magnetic storage are: Diskettes (floppy disks) Hard disks High-capacity floppy disks Disk cartridges Magnetic tape The primary types of optical storage are: Compact Disk Read-Only Memory (CD-ROM) Digital Video Disk Read-Only Memory (DVD-ROM) CD-Recordable (CD-R) CD-Rewritable (CD-RW) PhotoCD Magnetic Storage Devices How Magnetic Storage Works Formatting Disk Areas Diskettes Hard Disks Disk . | Types of Storage Devices lesson 9 This lesson includes the following sections: Categorizing Storage Devices Magnetic Storage Devices Optical Storage Devices Categorizing Storage Devices Storage devices hold data, even when the computer is turned off. The physical material that actually holds data is called a storage medium. The surface of a floppy disk is a storage medium. The hardware that writes data to or reads data from a storage medium is called a storage device. A floppy disk drive is a storage device. The two primary storage technologies are magnetic and optical. The primary types of magnetic storage are: Diskettes (floppy disks) Hard disks High-capacity floppy disks Disk cartridges Magnetic tape The primary types of optical storage are: Compact Disk Read-Only Memory (CD-ROM) Digital Video Disk Read-Only Memory (DVD-ROM) CD-Recordable (CD-R) CD-Rewritable (CD-RW) PhotoCD Magnetic Storage Devices How Magnetic Storage Works Formatting Disk Areas Diskettes Hard Disks Disk Capacities Other Magnetic Storage Devices Magnetic Storage Devices - How Magnetic Storage Works A magnetic disk's medium contains iron particles, which can be polarized—given a magnetic charge—in one of two directions. Each particle's direction represents a 1 (on) or 0 (off), representing each bit of data that the CPU can recognize. A disk drive uses read/write heads containing electromagnets to create magnetic charges on the medium. Random particles (no data stored) Current flow (write operation) Organized particles (represent data) Medium Write head As the medium rotates, the head writes the data. Magnetic Storage Devices - Formatting Before a magnetic disk can be used, it must be formatted—a process that maps the disk's surface and determines how data will be stored. During formatting, the drive creates circular tracks around the disk's surface, then divides each track into sectors. The OS (Operating System) organizes sectors into groups, called clusters, then tracks each file's location .