CDs and DVDs
The multimedia presentations combine text, visual graphics, pictures, images, video and audio.
Typically multimedia presentations are produced using special-purpose software, like Microsoft Powerpoint.
Once created, a multimedia presentation has to be delivered to its potential audience.
Multimedia delivery: handouts
One form of distribution of multimedia presentations is on removable recordable discs, like CDs, DVDs, USB sticks, etc.
Recordable CDs and DVDs can be burned with the desired content and an image can be printed on the disc itself. Burned and/or printed CDs and DVDs can be accompanied by printed booklets or covers and Cd/DVD jewel cases (jewel boxes).
The appropriate types of discs are CD-R (recordable – once recorded space cannot be retrieved or rewritten) and CD-RW (rewritable, with possibility for multiple use = erasure and writing). The respective DVDs are similarly of the types R (recordable) and RW (rewritable). Of these the rewritable variety discs are the more expensive.
Popular CD/DVD sizes
Discs vary by size and capacity. Currently there are two popular types of CDs/DVDs by size: 120 mm and 80 mm. The former are still the more popular by far, but the latter are gaining popularity recently. The 120 mm discs have the size of the standard audio CDs or the CDs on which software is distributed.
Besides the conventional 8 cm and 12 cm sizes there are discs shaped like business and credit cards. They are non-conforming to official CD specifications and consequently may not write and play back in all recorders or readers.
Popular CD/DVD capacities
The most popular CDs (120 mm) measure 84 minutes (with audio content) or 700 MB (of data). The 8 cm CDs measure 21 minutes and 185 MB respectively.
There are a few non-standard (meaning that they may not be readable/writable in all drives) capacities in circulation: 34 minute/300 MB (8 cm), 90 minute/790 MB and 99 minute/870 MB (12 cm) CD-R discs.
The popular DVDs are of the single-side variety (some special devices use double sided DVDs). The popular capacities in circulation are: 1.46 GB (8 cm), and 4.7 GB (12 cm) DVD-R discs.
Packaging CDs/DVDs: jewel cases (boxes)
A jewel CD case is the original compact disc case from 1982. It is a three-piece plastic case, measuring 142 mm × 125 mm × 10 mm, which usually contains a compact disc along with a CD cover or brochure and a back card.
The front lid contains tabs to keep any cover in place. The typical cover card or leaflet is 120 mm × 120 mm. The size of the back card (if any) is 150 mm × 118 mm. It is visible through the clear back and sides of the box.
Slimline jewel cases have become a common space-saving packaging for burned CD-ROMs. They measure 142 mm × 125 mm × 5 mm, and will generally fit two to a slot in a standard CD rack. They generally do not have room for a booklet, only a cover showing through the front of the case. Unlike the standard jewel cases, slimline cases are made of two pieces rather than three and do not have a place for a back label.
Smaller jewel cases are used for 8 cm CD and DVD media, slim ones as well. There are also larger DVD-style cases with a more book-like appearance. The simplest, least expensive package is a paper envelope, possibly with a transparent window to the envelope, or a plastic pocket.
Printable CDs/DVDs
CDs/DVDs the non-data containing side of which can be printed upon by special printers are known as printable. Visually they can be recognised by their completely white surface on the printable side.
There is also a special variety of “printable” disc, which are called LightScribe discs, due to the LightScribe technology which is supported by certain recorders. LightScripe printing is not colour printing and is similar to engraving an inscription or a logo onto the non-recordable surface of the discs.
