ACRN released by Linux Foundation is a flexible and lightweight open source hypervisor reference software. Intel provided most of the design and code for this project, and its rich experience and leading position in virtualization technology played a key role in the initial development of this hypervisor solution. ACRN is mainly composed of two parts: hypervisor software and device model, which supports many I/O devices. The design of ACRN is based on real-time and critical security, and is especially optimized for simplifying embedded development. This project provides a reference design framework for leaders in various industries, which can be used to build an open source embedded hypervisor, especially in the field of Internet of Things. In addition, open source projects generally allow users to see the original code and develop on this basis, so they are more secure.