An ultra-mobile PC (ultra-mobile personal computer or UMPC) was a small form factor version of a pen computer, a class of laptop whose specifications were launched by Microsoft and Intel in spring 2006. Sony had already made a first attempt in this direction in 2004 with its Vaio U series, which was however only sold in Asia. UMPCs are smaller than subnotebooks, have a TFT display measuring (diagonally) about 12.7 to 17.8 cm (5 to 7 inch screen), are operated like tablet PCs using a touchscreen or a stylus, and can also have a physical keyboard. There is no clear boundary between subnotebooks and ultra-mobile PCs. The first-generation UMPCs were simple PCs running Linux or an adapted version of Microsoft’s tablet PC operating system. With the announcement of the UMPC, Microsoft dropped the licensing requirement that tablet PCs must support proximity sensing of the stylus, which Microsoft termed “hovering”. Second-generation UMPCs use less electricity and can therefore be used longer (up to five hours) and also support Windows Vista. Originally code-named Project Origami, the project was launched in 2006 as a collaboration between Microsoft, Intel, Samsung, and a few others. After largely been supplanted by tablet computers, production of Ultra-mobile PC was discontinued in early 2010s.