Source of version: 2
Windows CE is the name of the core operating system that Windows Mobile devices use.
Also, Windows CE was the name of the original PDAs that were released in 1996.
The first devices were called Handheld PCs. They used MIPS and SH3 CPUs and had as little as 2 MB of ram as well as a 4MB of rom.
The second family of devices were called Palm-size PCs. They also used MIPS and SH3 CPUs and had as little as 4MB of ram and 8 MB of rom. The Palm-size PCs resemble the next generation called Pocket PCs. Originally the devices were called Palm PCs however Palm sued for copyright infringement and the name was changed to Palm-size PCs.
The versions are documented at http://www.pocketpcfaq.com/version.htm
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