In concept, the PDA, or the Personal Digital Assistant, is a combination of a scaled-down personal computer and a digital organizer. Before the PDA evolved to its present form, both approaches were actually tried. Psion 1, launched in 1984 by UK-based Psion, was an upgraded organizer with a single-line display. Computing power was added through the optional Science Pack that let you create your own programs. On the other hand, sub notebooks like the LG Phenom were attempts at scaling down the PC.

It was in 1993 with Apple’s Newton MessagePad that the PDA really emerged as a device that was effective. Apple’s approach was a new one. It created a device that functioned differently from a computer. The Newton did not use a keyboard or a mouse for data input; instead it used a stylus and depended on handwriting recognition. The stylus as the means for input has, since then, defined the PDA. The Newton also used its own operating system, the Newton OS, which was later discontinued. Anyhow, like the stylus, the Newton OS defined a new approach to OS design. Today, popular PDAs use one of three OSs: Pocket PC, PalmOS, or Symbian. Some use other OSs, but these have not had any impact worth mentioning here.

Pocket PC

This year Microsoft launched its Pocket PC to take on the Palm platform. The Pocket PC OS is faster and different, when compared to the earlier WinCE, and a number of devices running the Pocket PC OS have already appeared, like Compaq’s iPAQ H3600, Casio EM500, Casio E-115 and E-125, HP Jornada 540.

WinCE, which was meant more for the sub notebook than the PDA never really took off, and Pocket PC is Microsoft’s fresh attempt to storm the PDA market. Going by the initial reports, Microsoft is sitting on a pretty wicket here.