(1) For AI singularity, see
technology singularity.
(2) (Singularity) An experimental operating system from Microsoft for the x86 platform written almost entirely in C#, a .NET managed code language. Released in 2007, Singularity was a non-Windows research project.
Like Windows, there was only one address space, but for security and crash protection, Singularity ran each OS or application process in an environment called a "software-isolated process" (SIP). Unlike other OS architectures, SIPs and the interprocess communications between them were analyzed for compliance at compile time. In addition, when a program was installed, it had to include a manifest of actions that comply with certain rules.