SECONDARY STORAGE DEVICES

MAGNETIC TAPEData tape that stores large amounts of information that can only accessed sequentially. Commonly used for off-site backup in case of disaster. It takes long to retrieve information.

Floppy DiskPlastic case that holds a flat disk coated in magnetic material. It is divided into tracks and sectors. It has a relatively high access time.

Hard Disk/Hard DriveLarge capacity rigid magnetic disk used for storing data. It has metal disks called platters. Platters have read write heads that find the data on the hard drive. Data is stored in sectors on a particular track. Cylinders make reading data quicker.

PLATTERS

Cylinders

External Hard DiskA hard drive in an external case usually connected by a USB cable.

CDStands for Compact Disk. It is a circular shaped disk that has bumps that reflect light representing data. They are very light weight and can store large amounts of data.

DVDDigital Versatile Disk. A circular shaped disk that has bumps that reflect light representing data but using a different laser beam that allows more storage.

Flash DrivesThumb Drive, USB Stick, Key Drives, Jump Drives, Pen Drives. Small USB based storage that uses flash based memory. Extremely durable and reliable because of no moving parts.

Flash Memory CardsVery small and portable and comes in many different shapes and sizes. SD Cards are most popular.

Device InterfacesIDE – integrated Drive ElectronicSATA – Serial Advanced Technology AttachmentSCSI – Small Computer System InterfaceSAS – Serial Attached SCSI

COMPARISON TABLE