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Media. Media Compact Disk. A Compact Disc ( CD ) is an optical disc used to store digital data, originally developed for storing digital audio. The CD , introduced in 1982, remains the standard playback format for commercial audio recordings as of mid-2006.
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MediaCompact Disk • A Compact Disc (CD) is an optical disc used to store digital data, originally developed for storing digital audio. • The CD, introduced in 1982, remains the standard playback format for commercial audio recordings as of mid-2006. • An audio compact disc consists of one or more stereo tracks stored using 16-bit PCM coding at a sampling rate of 44.1 kHz. • Standard compact discs have a diameter of 120 mm or 80 mm. • The 120 mm discs can hold approximately 80 minutes of audio. • The 80 mm discs, sometimes used for CD singles, hold approximately 20 minutes of audio.
MediaCompact Disk • Compact disc technology was later adapted for use as a data storage device, known as a CD-ROM, (CD-R) and to include record-once and re-writable media (CD-RW). • CD-ROMs and CD-Rs remain widely used technologies in the personal-computer industry as of 2006. • The CD and its extensions have been extremely successful: in 2004, the annual worldwide sales of CD-Audio, CD-ROM, and CD-R reached about 30 billion discs
MediaMiniDisc • A MiniDisc (MD) is a magneto-optical disc-based data storage device initially intended for storage of up to 80 minutes of digitized audio. • The technology was announced by Sony in 1991 and introduced January 12, 1992, and is capable of storing any kind of binary data. • Minidiscs are popular in Japan as a digital upgrade to cassette tapes, but have not been as popular in the United States despite multiple marketing efforts by Sony. • Minidiscs were also somewhat popular for a time in the United Kingdom between 1998 and 2001, when a selection of Minidisc albums were available alongside CD and Cassette albums. • Minidiscs are now primarily used for recording.
Media DVD • DVD (also known as "Digital Versatile Disc“) is an optical disc storage media format that can be used for data storage, including movies with high video and sound quality. • DVDs resemble compact discs as their physical dimensions are the same (120 mm (4.72 inches) or occasionally 80 mm (3.15 inches) in diameter) but they are encoded in a different format and at a much higher density.
Media DVD Video • DVD-Video discs require a DVD-drive and an MPEG-2 decoder (e.g. a DVD-player, or a DVD computer drive with a software DVD player). • Commercial DVD movies are encoded using a combination of MPEG-2 compressed video and audio of varying formats. • Typical data rates for DVD movies range from 3–10 Mbit/s and the bit rate is usually adaptive. • The typical video resolution for an NTSC disc is 720 × 480, • PAL disc is 720 × 576.
Media DVD Video • The specifications for video files on a DVD can be any of the following: • All MPEG video must be 25 frames per second on PAL DVDs. • On NTSC DVDs MPEG-2 video can be either 29.97 frames per second or 23.976 frames per second, • MPEG-1 video can only be 29.97 frames per second.
MediaUSB flash drives • USB flash drives are flash memory data storage devices integrated with a USB interface. They are typically small, lightweight, removable and rewritable. Memory capacity typically ranges from 1 megabytes up to 64 gigabytes. • There are versions which use FireWire as well as USB, though these are less common.
MediaUSB flash drives • USB flash drives have several advantages over other portable storage devices, particularly the floppy disk. • They are generally faster, hold more data, and are considered more reliable (due to their lack of moving parts) than floppy disks. • Most flash drives are active only when powered by a USB computer connection, and require no other external power source or battery power source; they are powered using the limited supply afforded by the USB connection. • To access the data stored in a flash drive, the flash drive must be connected to a computer.
MediaTape • A tape drive, also known as a streamer, is a data storage device that reads and writes data stored on a magnetic tape • It is typically used for archival storage of data stored on hard drives. • Tape media generally has a favorable unit cost and long archival stability. • Instead of allowing random-access, tape drives only allow for sequential-access of data. • Tape drive must spend a considerable amount of time winding tape between reels to read any one particular piece of data. As a result, tape drives have very slow average seek times. • Despite the slow seek time, tapes drives can stream data to tape very quickly. For example, modern drives can reach continuous data transfer rates of up to 80 MB/s, which is as fast as most 10,000 rpm hard disks.
MediaTape • Tape drives can be connected to a computer with SCSI, parallel port,USB, FireWire or other interfaces. • Tape drives can range in capacity from a few megabytes to upwards of 800 GB. • Tape drives can be found inside autoloaders and tape libraries which assist in loading, unloading and storing tapes. • In the 1980s some forms of tape drives were used as inexpensive alternatives to disk drives, examples include the ZX Microdrive and Rotronics Wafadrive.