Optical storage devices CDs tend to be used for large files (but smaller than 1Gb) which are too big for a floppy disc to hold such as music and general animation. DVDs are used to hold very large files (several Gb’s) such as movie films. Both CDs and DVDs are portable i.e. they can be transported from one computer to another. Both can be used to store computer data. DVDs, CDs, Blu-ray Janelle Choo 10GM
Cd r / dvd r Applications which require a single ‘burning’ of data, e.g. CDs – recording of music downloads from the Internet, recording of music from MP3 format, recording of data for archiving or backup purposes. DVDs – recording of film movies and television programs. Used for recording. Disadvantages: Can't be erased and reused. Some DVD players won't play CD-Rs. Advantages: Cheap. Permanent - can't be erased accidentally. Burns fast. Playable on most CD players (for audio CDs). Janelle Choo 10GM
Many CD players, especially older ones, won't read CD-RWs.
Janelle Choo 10GM
Dvd ram Housed in a cartridge. Used in video recorders, camcorders and computer memory. Advantages: Long life — without physical damage, data is retained for an estimated 30 years. Can be rewritten over 100,000 times. Faster DVD-RAMs support fewer rewrites. Verification done in hardware by the drive, so post-write verification by software is unnecessary. Software verification is disabled in all current DVD Video Recorders. Disadvantages:
Less compatibility than DVD+RW and DVD-RW.
12x media is not reportedly available in Europe.
16x media may not be available anywhere except manufacturers' R&D laboratories.
DVD-RAM media have always been more expensive than other types of DVD.
Janelle Choo 10GM
Hddvd Used in video recorders and computer memory as well as games consoles. HD DVD-R / -RW / -RAM HD DVD-R is the writable disc variant of HD DVD, available with a single-layer capacity of 15 GB or a dual-layer capacity of 30 GB. HD DVD-RW is the rewritable disc variant of HD DVD with equal storage capacity to an HD DVD-R. The primary advantage of HD DVD-RW over HD DVD-R is the ability to erase and rewrite to an HD DVD-RW disc, up to about 1,000 times before needing replacement, making them comparable with the CD-RW and DVD-RW standards. This is also of benefit if there are writing errors when recording data, as the disc is not ruined and can still store data by erasing the faulty data. HD DVD-RAM was the proposed successor to DVD-RAM for random access on optical media using phase-change principals. It would hold 20 gigabytes per layer instead of 15 gigabytes for HD DVD-R, due to differences in recording methods used, yielding a higher density disc. Janelle Choo 10GM
Blu-ray Blu-ray, also known as Blu-ray Disc (BD), is the name of a next-generation optical disc format. The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data. This extra capacity combined with the use of advanced video and audio codec will offer consumers an unprecedented HD experience. Disadvantages: Expensive!!! Low-Quality. Advantages: Huge storage capacity. Backwards compatibility. The Disc Association is encouraging manufacturers to make the players fully backwards compatible. That will allow users to both read and write on CDs, DVDs, and, obviously, Blu-ray discs. Quality support Sony and Philips might be the strongest backers of Blu-ray, but other major corporations have announced future plans to support the technology. Janelle Choo 10GM
Flash Memory cards Used in digital cameras, palmtops, mobile phones, MP3 players. A memory card or flash memory card is solid-state electronic flash memory data storage device capable of storing digital contents. These are mainly used with digital cameras, handheld and Mobile computers, mobile phones, music players, digital cinematography cameras, video game consoles, and other electronics. They offer high re-record-ability, power-free storage, small form factor, and rugged environmental specifications. Disadvantages:
Has small capacity in comparison to other memory card formats.
Has less popularity among cameras, card readers and in other accessories.