Over the years, people have tried to transfer information from one computer to another in a dizzying number of ways. Here's a look at some of the best, along with others that time forgot.
The optical disc
The compact disc, which originated as a digital audio storage medium, emerged from a joint Sony/Philips project and first reached the market in 1982.
The format stores digital data in the form of pits moulded into the top of a plastic disc that has a reflective backing.
A laser reads the pits. Because CDs are digital, they are perfect for storing computer data, and it wasn't long before Sony/Philips adapted the format to create computer CD-ROMs, producing the first commercial CD-ROM drive in 1985.
The 5cm optical disc has undergone further development during the past 25 years, resulting in higher-capacity discs such as DVD, HD-DVD, and Blu-ray.
More significant was the introduction in 1988 of the CD-Recordable (CD-R), which let users write their own data to the disc.
In the late 1990s, as optical media got cheaper, this form of storage supplanted floppies in handling most day-to-day data transfers.
Photos: Benj Edwards/Sony
Like CDs, magneto-optical (MO) discs are designed to be read optically with a laser.
But unlike CDs, which users can't write to at all, and CD-Rs, which users can write to only once, most MO discs permit the user to write and erase data on a disc multiple times.
They accomplish this by means of a special magnetic process that works in conjunction with a laser to store data.
The first widely known magneto-optical drive shipped with the NeXT Computer (1988, lower right) and used 256MB rewritable media.
The best-known MO format is the Sony MiniDisc (top middle, 1992), an audio medium that also has a less popular computer-capable cousin known as MD-DATA (upper left).
Various MO drives and discs remain in production, but their relatively low capacity and relatively high cost make them niche products.
NEXT PAGE: Iomega and the zip drive