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Blank Media Glossary

Ralph Graves is one of Crutchfield's blog editors, and part of the company's social media team. He writes about home audio/video gear, specializing in Apple-related and wireless technologies. Ralph holds a master's degree in music composition, and his works have been released on various labels. He's served as product manager for an independent classical and world music label, produced several recordings, and worked extensively in public broadcasting. Since 1984 he's hosted a weekly classical music program on WTJU, and is also active as a blogger and podcaster.

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The definitions on this page are divided into three main media categories — Blank discs, Blank tapes, and Blank memory cards — followed by a short list of General terms.

Blu-ray Discs Have a lot of high-def footage from your HD camcorder? You can use a Blu-ray recorder to copy your home movies to recordable discs and watch them with a compatible Blu-ray player.

Blank discs

BD-R (recordable Blu-ray Disc)
BD-Rs are "write-once" recordable Blu-ray Discs. BD-Rs can store up to 50 gigabytes of information (about the same as ten regular DVD-Rs), and are primarily used for high-definition video and large multi-media files. BD-Rs can only be burned with a Blu-ray Disc™ recorder, and can only be played back on compatible Blu-ray players.

A dual-layer BD-R can hold over 21 hours of high-definition MPEG2 video, or up to 46 hours of standard-definition television recordings.

BD-REs are an erasable, re-recordable version of BD-R. Like BD-Rs, they can store up to 50GB of information, can only be burned with a Blu-ray Disc drive in a compatible computer, and are primarily used for high-definition video and large multi-media files. Once a BD-RE disc has been recorded and finalized, it can be played back in some compatible BD players and most computer BD-R drives.

CD-R (audio and data)
CD-Rs are recordable CDs that can be "written to" or recorded upon once. Because of their low cost, these discs are popular for a variety of uses: making audio recordings, storing compressed music files (like MP3 and WMA), and archiving many other types of data.

CD-Rs are designated for either "audio" or "data" use. Blank discs labeled "audio" can be used with home CD recording decks as well as computer CD-R/W drives, and cost more than data-grade CD-Rs. Blank CD-Rs designated as "data" tend to cost less than audio CD-Rs, but can only be recorded to using a computer CD-R/W drive. Keep in mind that extremely inexpensive discs may be prone to unreadability and higher error rates.

When an audio CD-R has been recorded and finalized, the disc can be played like a regular CD in almost all home, car, portable players, and computer disc drives. However, a CD-R can never be re-recorded. CD-Rs commonly hold 74 minutes of music (650 megabytes of data), but 80-minute (700-megabyte) discs are also available.

CD-RW (audio and data)
Unlike CD-Rs, CD-RWs are rewritable CDs that can be written to over and over again. When you make a recording on an audio CD-RW and finalize it, you can play it like a regular CD in many types of players. If you want to change it, you can erase it and re-write to it (usually about 1000 times).

Otherwise, CD-RWs are similar to CD-Rs. CD-RWs are designated for either "audio" or "data" use. Blank discs labeled "audio" can be used with home CD recording decks as well as computer CD-RW drives, and cost more than data-grade CD-RWs. Blank CD-RWs designated as "data" tend to cost less than audio CD-RWs, but can only be recorded to using a computer CD-RW drive. Keep in mind that extremely inexpensive discs may be prone to unreadability and higher error rates.

CD-RWs commonly hold 74 minutes of music (650 megabytes of data); 80-minute (700-megabyte) discs are also available. However, CD-RW discs are not as widely compatible with home, car, and portable players as CD-Rs, and tend to cost more.

DVD-R is a "write-once" recording format that allows you to burn your own DVD video discs, using a compatible DVD recorder or computer DVD-writing drive. Once finalized, DVD-R discs can be played back in most DVD players and computer DVD-ROM drives. DVD-R discs cannot be re-recorded.

A single-sided DVD-R disc offers 4.7GB of storage, allowing you to record up to 120 minutes of studio-quality MPEG2 video. You can also find double-sided DVD-Rs, which can hold 9.4GB per disc.

When shopping for DVD-R media, keep in mind that there are two different versions of the DVD-R format: a "general" version, sometimes referred to as "DVD-R(G)"; and an "authoring" version, sometimes called "DVD-R(A)." The general version is used in all DVD home recording decks and computer DVD-RW drives, while the authoring version is intended for professional applications. DVD-R(A) discs are not compatible with DVD-R(G) recorders, and vice versa.

DVD+R is a "write-once" recording format that lets you burn your own DVD video discs, using a compatible DVD recorder or computer DVD-writing drive. Once finalized, DVD+R discs can be played back in many newer DVD players and computer DVD drives. DVD+R is a version of DVD+RW although it can be compatible with a few more home players and computer DVD-ROM drives than the rewritable DVD+RW disc.

DVD-RAM lets you create your own DVD video discs. DVD-RAM discs are rewritable, and can be erased and re-recorded up to 100,000 times. A DVD-RAM disc can store up to 4.7 gigabytes of data — approximately 60 minutes of of ultra-high-quality MPEG2 video, 2 hours of standard mode video, or 6 hours of VHS-quality video. DVD-RAM recorders feature a very high data transfer rate (22.16 Mbps), and employ random access storage and retrieval, like a computer's hard disk drive. This method of handling data gives DVD-RAM some handy capabilities that you don't get with other recordable DVD formats.

For instance, some DVD-RAM decks give you simultaneous, independent playback and recording — you can watch one recorded program while a different one records, or watch a program from the beginning while a later portion of the same program continues recording. Once you've recorded a series of scenes or programs onto a DVD-RAM disc, you can rearrange the playback order, or remove unwanted segments altogether.

However, there's a bit of a trade-off for the added flexibility. DVD-RAM discs can be used in a few component DVD recorders and an increasing number of DVD-RW drives — but they're not compatible with most regular DVD players and DVD-ROM drives. So, for instance, if you want to record home movies to a DVD disc that you can send to a family member or friend, consider using the more widely compatible DVD-R format.

Camcorder Rewritable mini DVD-RW discs let you erase unneeded scenes and re-record your footage. After you've filled up the disc and transferred the footage to your computer, you can erase the entire disc and record another event. Each disc can be reused up to 1,000 times.

The DVD-RW format is an erasable, re-recordable version of DVD-R. A single-sided DVD-RW disc offers 4.7GB of storage, allowing you to record up to 120 minutes of studio-quality MPEG2 video (with a compatible computer DVD-RW drive or home DVD recorder). DVD-RW discs can be erased and re-recorded up to 1,000 times.

Once a DVD-RW disc has been recorded and finalized, it can be played back in some regular home DVD players and computer DVD-ROM drives.

DVD+RW is another rewritable DVD recording format. It shares several similarities with DVD-RW: single-sided discs offer a capacity of 4.7GB (about 2 hours of studio-quality video); they can be erased and re-recorded up to 1,000 times; and once a disc has been recorded and finalized, it can be played back in some regular home DVD players and computer DVD-ROM drives.

These small re-recordable 2-1/2" discs were developed by Sony as an alternative to CD-R/Ws. Most MiniDiscs (MDs) hold up to 74 minutes of music, though long-play discs provide up to 80 minutes, and some MiniDisc recorders include features that can extend record time even further.

MiniDisc's chief advantages are its high recording capacity, sturdiness, small size, low price, and the fact that it can be re-recorded upon almost infinitely. Another advantage is the flexibility to rearrange the song playback order without re-recording the entire MD. However, MDs are not as widely supported these days.

Some camcorders record digital video to mini DVD-R and DVD-RW discs, smaller 80mm versions of standard 120mm DVD discs. Mini DVD-Rs are once-recordable discs that come in both single-sided and double-sided formats. A single-sided disc can store up to 30 minutes of video at the highest recording quality setting, while a double-sided disc can store up to 60 minutes of video at the highest quality setting. Like other media, these discs can hold more video when it's recorded at a lower setting. Mini DVD-RWs have the added advantage of letting you record and re-record footage up to 1,000 times. For more info, see our article about DVD camcorders.

Most newer DVD players can play mini DVD discs — a great plus if you want to easily show off your new home footage to family and friends. Variants of the 80mm mini DVD have also been used in the gaming industry, like with Nintendo's GameCube™ system.

Blank tapes

Audio cassette
The audio cassette records an analog audio signal as a series of electrical impulses on a miniature spool of 1/8" magnetic tape (attached to a pair of hubs inside the cassette's plastic shell). The cassette deck uses a mechanical, motor-driven transport to rotate the hubs, passing the tape across the deck's playback and record heads.

Blank cassettes are available in a range of capacities, with total recording times usually between 60 and 100 minutes, or longer. There are 3 types of tapes (in order of increasing audio quality): Type I (Normal), Type II (CrO2), and Type IV (Metal). Not all cassette decks allow recording with metal type tapes; see your owner's manual for compatibility info.

Digital8 camcorders use inexpensive and easy-to-find 8mm and Hi8 cassettes for recording and playback. Digital8 itself isn't really a blank media format, but you'll find tapes labeled for Digital8 use. A 120-minute Hi8/8mm tape yields one hour of recording when used with a Digital8 camcorder, giving you essentially the same picture quality you get with Mini DV (500 lines of horizontal resolution).

8mm and Hi8 cassettes are medium-sized — smaller than VHS, but larger than Mini DV. When deciding between Hi8 and 8mm for your Digital8 camcorder, keep in mind that the digital video quality on Hi8 and 8mm is the same. However, spending a little extra on better-quality Hi8 cassettes may reduce the tape glitches that can happen over time.

Digital VHS (D-VHS)
Unlike regular VHS recorders, digital VHS recorders are capable of recording HDTV programs at full high-def resolution. To capture HDTV signals with all their detail, D-VHS VCRs use specially formulated D-VHS tapes. These tapes can also be used to make Super VHS and standard VHS recordings.

As with regular VHS and S-VHS cassettes, D-VHS tapes come in a variety of recording capacities. The maximum available capacity for a single tape is up to 4 hours of digital recording in highest-quality mode, 8 hours in "standard" mode, 24 hours in the lower-res "LS3" mode, or up to 40 hours of S-VHS-quality analog video.

8mm video format
see Digital8

Hi8 video format
see Digital8

Mini DV Mini DV tapes let you perform precise, frame-by-frame editing on your home video footage.

Mini DV
Mini DV is a video cassette designed for use in Mini DV digital camcorders. The picture quality of digital video recorded on a Mini DV cassette is basically identical to the quality recorded on a Hi8 or 8mm cassette by a Digital8 camcorder. However, Mini DV tapes are tiny — literally pocket-sized — which allows for greater portability. They're available in lengths of 30 and 60 minutes. Recording in LP mode lets you extend total recording time with a 60-minute tape to 90 minutes.

[Shop our selection of Mini DV tape.]

Super VHS (S-VHS)
Super VHS cassettes look like standard VHS cassettes, but they feature a special high-density tape formulation which allows the S-VHS format to deliver 400+ lines of video resolution, instead of VHS's 240 lines. Recording at this higher resolution requires a Super VHS VCR.

S-VHS picture quality can also be achieved using standard VHS tapes using a special recording format available on some JVC VCRs, known as Super VHS ET.

VCRs have been mostly replaced by DVD recorders and DVRs, though you can still find some VHS/DVD combination players if you're holding on to a large collection of VHS tapes at home. VHS is capable of delivering 240 lines of video resolution, along with stereo sound that's nearly as good as CD (in dynamic range and frequency response).

VHS cassettes are roughly the size of a paperback book. Blank tapes usually feature either 120 minutes or 160 minutes of recording time at the highest recording speed (6 hours or 8 hours at the slowest speed).

[Shop our selection of VHS tapes.]

Blank Memory Cards

CompactFlash® card
An extremely popular form of re-recordable flash memory originally developed by SanDisk. CompactFlash cards are used in some digital cameras, PDAs and handhelds, and other small portable digital devices. They are available in a range of capacities, from 256MB to as much as 8GB.

There are two versions of the CompactFlash card, which have slightly different sizes: Type I cards are thinner, Type II are thicker. Type I cards will operate in either Type I or Type II CF card slots, but not vice versa.

[Shop our selection of CompactFlash cards.]

MagicGate™ Memory Stick
Sony's proprietary form of SDMI-compliant flash memory. The MagicGate Memory Stick is based on the "original" Memory Stick but has an extra chip built-in to recognize and comply with the requirements imposed on copyright-protected materials.

MagicGate Memory Sticks are used primarily in digital audio players. They can also be used with devices that use "original" Memory Stick; however, an original Memory Stick can not be used in devices that require a MagicGate Memory Stick. Like other flash memory formats, they are small, durable, solid-state, have fast read/write speeds, and are available in a variety of capacities.

Memory Stick®
Originally developed by Sony, Memory Stick is a form of flash memory used in digital cameras, digital camcorders, handhelds, printers, and more. Sony makes a special form of the SDMI-compliant Memory Stick for use with digital music players, called MagicGate Memory Stick; these also work in devices that use "original" Memory Sticks.

[Shop our selection of Memory Sticks.]

microSD™ card The microSD card is an even smaller version of the miniSD card. About the size of a fingernail, the microSD card is designed for use with cell phones, handheld GPS devices, and other small electronics. Usually microSD cards come with two adapters — one for use with a miniSD card slot, and the other for a standard SD card slot. Storage capacities for the microSD card range from 64MB to 4GB.

miniSD™ card
The miniSD card is a more compact version of the Secure Digital card. Designed for use in compact portables such as cellphones, MP3 players, and digital cameras, the card can be read by most devices that are compatible with a standard-sized SD card. Almost all miniSD cards come with an adapter so they can be inserted into a full-sized SD card slot. Like SD cards, storage capacities for miniSD cards range from 16MB to 4GB.

MultiMediaCard® (MMC)
A form of removable flash memory, MultiMediaCards (or MMCs) were developed by SanDisk and are supported by several audio/video manufacturers for a variety of uses. Like other flash memory cards, they are small (about the size of a postage stamp), durable, provide solid-state memory and fast read/write speeds, and are available in a range of capacities.

MMCs have been gradually supplanted by another form of digital storage called SD (Secure Digital) memory. However, SD devices have backward compatibility, so you can use your existing MMC media in a player that accepts SD cards and does not have copy protection requirement.

Blank Memory Cards SD cards are a common form of blank memory card, and range in size from 256MB to 4GB. Some devices are also compatible with SDHC cards, which offer up to 32GB of storage.

SDHC card
The Secure Digital High Capacity (SDHC) card is an increased capacity version of the standard SD card. Because SDHC cards use a more efficient method of storing data than SD cards, they have capacities of 4GB to 32GB. SDHC cards will only work in SDHC-compatible devices.

[Shop our selection of SDHC memory cards.]

Secure Digital® (SD) card
A Secure Digital (SD) card is an SDMI-compliant flash memory card used in some digital cameras, memory players, and other portable digital devices. Like other SDMI-compliant cards, an SD card uses an extra chip to recognize and comply with the requirements imposed on copyright-protected materials.

[Shop our selection of SD memory cards.]

SmartMedia™ card
SmartMedia is a form of flash memory originally developed by Toshiba, and used in some digital cameras, portable digital music players, and other devices. SmartMedia cards are available in a range of storage capacities. Like other flash memory cards, they provide portable, durable, solid-state memory, have fast read/write speeds, and are supported by many manufacturers.

xD-Picture Cards™
xD-Picture Cards are among the smallest and fastest available forms of flash memory. As the name implies, these cards are used primarily for picture storage with some brands of digital cameras. They're extremely portable — roughly thumbnail-sized — and are available in a range of capacities.

xD-Picture Cards boast speedier read/write access than many other forms of flash memory. They're also economical in terms of power consumption, allowing you to read from or write to the card more often between battery charges (other factors being equal).

General terms

Embedded memory
Usually a type of flash memory or hard drive, embedded memory is a form of internal digital storage that's built directly into a device. When it comes to audio/video gear, embedded memory is most commonly used in portable MP3 players, but is also used with other devices (such as digital cameras and camcorders). Although some embedded memory can be replaced with the help of a technician, it's not made to be easily removable and transferable, like memory cards.

Embedded memory is popular because you have no memory cards or discs to carry around. Plus, it can be less expensive to buy an item with embedded memory rather than buying a player and some removable media. On the other hand, a player or camcorder that only uses embedded memory is relatively limited in terms of total music (or photo and video) storage. As a result, some of these devices offer an expansion slot for adding removable media and thereby increasing storage.

Flash memory
A form of digital storage developed in 1988 for use in personal computers and PC peripherals. Flash memory gets its name because sections of memory cells within the microchip are erased in one simultaneous action, or "flash." Today, flash memory is commonly used with portable digital music players, handhelds/PDAs, digital cameras, and for storing digital still pictures in digital camcorders.

It may be embedded or removable. There are a number of removable cards available from different manufacturers, including CompactFlash, Memory Stick, and Secure Digital cards. Removable flash memory usually offers the following characteristics: a sturdy case, the skip-free stability of solid-state memory, small size, and high memory capacity. It also features very fast read/write speeds which result in a higher cost than many other kinds of media.

[Shop our selection of flash memory drives.]

Hard drive
Also known as a hard disk drive or HDD, a hard drive is a device that digitally stores data on rapidly rotating disks with magnetic surfaces. They're a popular form of data storage since they're a relatively fast storage medium and can hold large quantities of information. Some hard drives can accommodate up to a terabyte or more of data.

Initially developed for computers, they're now built into other devices, like camcorders and game consoles, that require a large amount of storage space. Hard drives are most commonly used as a form of embedded memory, although external hard drives are popular for computers as a back-up in case the primary hard drive runs out of memory or fails.

Removable media
Any kind of media which isn't built into the device it works with is considered removable media. Most audio and video recorders and players use removable media, such as CD-Rs, VHS tapes, DVDs, or some type of flash memory card. Some devices, such as certain MP3 players, use non-removable, embedded media.

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