Consumers hate cables – and many Y2K era PCs had over a dozen of them.

Although obviously wire and connector free, wireless linking traditionally involves tradeoffs between power, range and speed.

Thus low power modules like the 433MHz units we’ve recently featured have fair range but only slow data speeds, while faster rates (900MHz cellular, etc) come with higher power demands, not easily met by batteries.

Get used to the ZigBee logo... you're going to see a lot more of it shortly!

Much higher frequencies, such as the license-free 2.4GHz slot, offer greater bandwidth so more data can be squeezed into the same signal spectrum. However microwaves are very line of sight, so ranges may be greatly reduced. Phew – it’s all compromises...

Acting in a similar manner to line-of-sight microwaves, infrared data remained the only easy wireless technique five years ago, although its need for clear links meant IR could never punch data pathways through walls, filing cabinets . . . or even paper.

To overcome this limitation, WiFi (IEEE802.11x) – which itself has undergone three recent revamps (a,b,g with "n" due this year) – and Bluetooth (IEEE802.15.1) evolved.

Bluetooth, although initially a sleeper, now features in almost all new cellular phones and such consumer peripherals as headsets, photo printers and PDAs.

The Bluetooth title incidentally honours tenth-century Viking King Harald of Denmark, famed for feasting on blueberries until his teeth apparently were stained blue. His administration skills however were even more legendary, since for a period (no doubt in their blueberry off season) he managed to unify the war-mongering provinces of Scandinavia to work together (maybe raiding neighbouring blueberry patches!), much in the way that today’s Bluetooth seamlessly links cameras, PCs, headsets, and cell phones etc.

You may groan with the near-
bewildering rate of progress and worry about security and 2.4GHz "RF smog" but now there’s a further offering.