Library Operating System (LibOS) is a type of operating system that runs in the address space of applications, allowing for a small, fixed set of abstractions to connect the library OS to the host OS kernel. This approach offers the promise of better system security and more rapid independent evolution of OS components. LibOS can run significant applications, such as Microsoft Excel, PowerPoint, and Internet Explorer, with significantly lower overhead than a full VM. It can also address many of the current uses of hardware virtual machines at a fraction of the overheads. 1

LibOS is lightweight, with extremely short startup time, and can be used to run Linux programs, making it a versatile option for various applications. It is designed to provide compatibility and sandboxing without the need for VMs, making it a lightweight alternative to containers and VMs. 1

The Library Operating System for Linux was announced on the Linux kernel mailing list, indicating its official recognition and support within the Linux community.