Windows 10 on ARM is a version of the Windows 10 that’s designed to run on ARM architecture-based processors such as Qualcomm Snapdragon. Microsoft partnered with Qualcomm to bring Windows 10 to ARM-based Snapdragon processors in 2017. Samsung’s next-gen Galaxy Book lineup will be based on its very own ARM chip and it could be announced later this year or next year depending on the feedback from its internal testings. Samsung has also prototyped Exynos 990 for PCs, but the company wants to go for a new chip based on ExynOS 1000, which offers better performance.
Source: https://www.bleepingcomputer.com/news/technology/samsung-is-reportedly-building-an-exynos-cpu-for-windows-10-pcs/