CD-R is a short form of "CD-Recordable", meaning recordable CD. In the past, users could only read the data on a CD-ROM. If users wanted to record data onto a CD, they had to ask assistance from a factory and do so in large quantities. With CD-R however, individuals can save data on a CD and produce a format that is exactly the same as that of a standard CD-ROM. But once made, the recorded sections of a CD cannot be recorded over, and due to different materials used, the colors of CD-R vary between gold, blue and green, unlike the silver of a standard CD-ROM .
CD-RW is short form for "CD- Rewritable", in other words, a rewritable CD. The special feature of CD-RW is that the recorded sections can be cleared and reused for re-recording. Of course, users cannot rewrite the CD-RW to an infinite number of times. Typically, each CD-RW can be rewritten about 1,000 times.
A color CD-R also known as Colored Substrate CD-Rs available in Black, Red, Blue, Orange, Purple, etc. are produced by adding a dye color to the clear plastic substrate during the manufacturing process. There is no difference in performance with these discs because although we humans see the full spectrum of visible colors on the discs, the laser has a much narrower vision. Our Neon and Black Onyx CD-Rs are the same quality as our data CDs.
Burning a CD using a burner(writer) with a writing speed of 4X will take about twice as long as burning the same CD using a burner with a writing speed of 8X. Usually A CD burner(writer) with a higher writing speed is more expensive than the one with lower speed.
The Orange Book specifies a Standard value of approximately 1,000 times. However, the actual number achieved on CD-RW media indicate it is possible to perform several thousand re-writes.
DVD once stood for digital video disc or digital versatile disc, but now it just stands for DVD -- the next generation of optical disc storage technology. DVD is essentially a bigger, faster CD that can hold cinema-like video, better-than-CD audio, and computer data. DVD aims to encompass home entertainment, computers, and business information with a single digital format, eventually replacing audio CD, videotape, laserdisc, CD-ROM, and video game cartridges. DVD has widespread support from all major electronics companies, all major computer hardware companies, and all major movie and music studios. With this unprecedented support, DVD has become the most successful consumer electronics product of all time in less than three years of its introduction.
DVD-R (which is pronounced "dash R" not "minus R") uses organic dye technology, like CD-R, and is compatible with most DVD drives and players. First-generation capacity was 3.95 billion bytes, later extended to 4.7 billion bytes. Matching the 4.7G capacity of DVD-ROM was crucial for desktop DVD production. In early 2000 the format was split into an "authoring" version and a "general" version. The general version, intended for home use, writes with a cheaper 650-nm laser, the same as DVD-RAM. DVD-R(A) is intended for professional development and uses a 635-nm laser. DVD-R(A) discs are not writable in DVD-R(G) recorders, and vice-versa, but both kinds of discs are readable in most DVD players and drives. The main differences, in addition to recording wavelength, are that DVD-R(G) uses decrementing pre-pit addresses, a pre-stamped (version 1.0) or pre-recorded (version 1.1) control area, CPRM, and allows double-sided discs. A third version for "special authoring," allowing protected movie content to be recorded on DVD-R media, was considered but will probably not happen.
It is a material similar to that of CD-R media.
DVD stands for Digital Versatile/Video Disc, DVDR stands for DVD Recordable and DVDRW for DVD ReWriteable. If you're familiar with regular audio/music CDs, then you will know what a DVD looks like. A single layer (DVD-5) DVD stores up to 2 hours of very good quality DVD-Video, including several audio tracks in formats like stereo, Dolby Digital or DTS and also advanced menu systems, subtitles and still pictures that can be played by standalone DVD Players and computer DVD-ROMs. If you choose to lower the video quality it is possible to store several hours video on a DVD using low bitrates and low resolution with video quality more like SVCD,CVD or VCD. It is also possible to have up to 4.38* GB ordinary data or mix DVD-Video and data on a DVD that can be played by computer DVD-ROMs.
FAQ Memory Cards
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1. What is the difference between the SD Memory Card and the MultiMedia Card? How are they related to each other?
A: SD Memory Card and MultiMediaCard share the similar physical dimensions, which allows upward compatibility such that MultiMediaCard can be inserted into SD Memory Card slot. Further, SD Memory Card has various advantages over the MultiMediaCard, such as content protection, planned capacity growth, high-speed data transfer, and a write protect switch. The SD memory Card distinguishes itself further as a true network platform and has defined a variety of application data formats which ensures compatibility between devices which adhere to these SD Application Standards. Application standards have been defined for many types of audio, video and document files among others types.
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2. Can SD Memory Cards be used with MP3 players on the market?
A: No, they cannot use the SD Memory Card. They cannot be physically inserted, and the logic format is different. Conversely, even though a MMC from a MP3 player can be inserted in a SD Audio player, it cannot be replayed.
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3. What is the difference between the SD Memory Card and the miniSD Card?
A: Logically and electrically, the miniSD? Card and the SD Memory Card are identical. Only the form factor, size, and number of pins of the miniSD? Card are different from the standard SD Memory Card. (Two additional pins are reserved for future use.)
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4. Will the miniSD Card replace the current SD Memory Card?
A: No, not at all. The miniSD? Card was designed to meet a special requirement from some of the mobile phone companies in Japan for the smallest possible memory card size.
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5. What is SD card?
A: A Secure Digital (SD) card is a tiny memory card used to make storage portable among various devices, such as car navigation systems, cellular phones, eBooks, PDAs, smartphones, digital cameras, music players, camcorders, and personal computers. An SD card features a high data transfer rate and low battery consumption, both primary considerations for portable devices. It uses flash memory to provide nonvolatile storage, which means that a power source is not required to retain stored data.