It's not the netBook.
The model shown in the image is the netBook Pro, which was released in late 2003 (Wikipedia says OCT-2003) and runs some version of WinCE. The chassis was almost identical, but this new version also had USB support, a 16-bit touch-screen display with a higher resolution, and better CPU and RAM specs too. Granted, WinCE wasn't everyone's flavour of the month back then, but for its target market, it was a good, pragmatic, choice.
The original netBook was based on EPOC32—the direct ancestor of today's Symbian OS. I used to own one of these, as well as its 'consumer' variant, the "Series 7". This original model of the netBook was released in 1999.
(My netBook spent its final years as a bedside alarm clock, with the advantage of also being an instant-on mini notebook so I could jot down any ideas I had during the night without having to faff around with lights, pens and bits of paper. And very useful it was too. My Macbook Pro performs this duty now.)