XenOS means "eXtendable Environment Network Operating System". It is (will be...) a real time, multitasking, protected mode operating system for i386 and compatibles. Its intended use are scientific applications such as data aquisition and process control. Each application program can contain several tasks, each one with its own resources. Tasks asking for real time rights cause all other tasks to be suspended until the real time task releases its rights. Thus, only one task at a time can have real time rights. Real time rights have to be granted by the user by configuring the application propertys. New (and unknown) application programs do not have any system specific rights. Depending on their rights, application programs may have full, quick and easy access to the computers hardware.