When you consider that only a few years ago a floppy disc could hold no more than 20 average business reports and a system backup to tape almost took as long as copying the information by hand, it is obvious that the technology in the future will be astonishing.

One of the key players in this market in SA is Rectron, a distributor of PC components and peripheral devices to more than 6 000 dealers and resellers across the country.

CEO Mark Lu maintains that, in the immediate future, the CD writer will dominate the data storage market, and it will continue to be one of the best storage media available.

He says CD-RW (rewriteable) drives represents the latest stage in the evolution of recordable CD media that began a few years ago with CD-R (recordable) drives.

"Before that," he explains, "there were just two members of the CD family, the audio CD and the CD-ROM. Both are read-only formats, since the data is written to the disk during the manufacturing process as a pattern of indentations in an aluminium layer.

"Since the pits - the indented areas - have a different reflectivity from the lands - the non-indented areas - the data can be read back using a laser beam.

"A user-recordable CD for data storage - the CD recordable [CD-R] - was introduced in the early nineties and represented the first major breakthrough in this arena from a technology perspective."

Turning to how this was achieved, Lu says the disk had a gold layer on which a transparent organic chemical was deposited. This chemical is unaffected by normal sunlight, but can be made opaque by shining a high-powered laser onto it. The gold shows through the transparent areas so that they will appear reflective, whereas the opaque areas will absorb light.

"The difference in reflectivity is similar to the difference between the lands and pits of a CD-ROM, so that, once written, a CD-R disk can be read using an ordinary CD-ROM drive," he notes.

According to Lu, CD-R drives failed to reach the mass market in any sizable volumes because of the high price of the recorders, the high price of early blank disks and the fact that it was a WORM format (write once, read many).

"Once a disk had been written to, it couldn't be reused. This was a significant hurdle to be overcome, but with the introduction of CD-rewriteable [CD-RW] technology, it was - and successfully so.

Looking at the technology behind the CD-RW, Lu explains: "A CD-RW disk has a layer consisting of silver, indium, antimony and tellurium. By heating and cooling this chemical mixture in different ways, it can be made either crystalline or amorphous and the process is reversible many times.

"Since the crystalline form is more reflective than the amorphous form, this lends itself, once again, to being read using a laser."

Lu maintains that the latest drives on the market today are the most versatile of units, being able to write to both CD-R and CD-RW disks, read all variants of the CD and can be bought for less than R2 000 at a retail store.

He says that when opting for a CD-RW unit, there are two main criteria to address: Write speed and type of connection.

"The write speed of a CD-RW drive is expressed as a multiple of the speed of an ordinary audio CD. Ideally, a 4X drive should be able to copy a 60-minute music CD onto a blank CD-RW disc in 15 minutes, while an 8X drive should take half that long," he says.

While 16X and 24X have become the standard in the past year, Lu says manufacturers that Rectron represent in SA have begun to introduce 40X units and the 48X benchmark should by reached by mid-2002.

"The technology in the optical devices arena does not stand still," he says, pointing to DVD (Digital Video Disk) technology, which has arrived, accompanied by much fanfare, and is threatening to make a significant impact on the CD market.

Lu says that while many market watchers predict that DVD will replace CD - as it offers up to 17Gb of storage compared to the CD's 600Mb - the reality maybe somewhat different - particularly in the short-term.

"DVD video players have been on the market for a year or so now and many PCs are presently being shipped with a DVD-ROM drive in place of the CD-ROM drive, so it's reasonable to assume a rewriteable variant of the DVD for data storage will eventually become the de facto standard.

"Taking all this into account, some people might consider it short-sighted to buy a CD writer now, but there are, nevertheless, a couple of reasons to moderate this view," he says.

"First of all, DVD-ROM drives are able to read CD-ROM, CD-R and CD-RW disks, so there is no obsolescence issue here. Second, standards wars have delayed the launch of a rewriteable DVD format.

"Although it looks as if DVD-RAM has successfully fought off the rival DVD-RW and DVD+RW formats, and although some DVD-RAM drives are now on the market, there's currently a large price differential when they are compared with CD writers."