Phantom OS is an operating system (OS) made by mostly Russian programmers (with help of some Uzbeks). It is based on a concept of persistent virtual memory, and uses a virtual machine, managed code, and bytecodes. It is one of a few OSes not based on classic concepts of Unix-like systems. Its primary goal is to achieve simplicity and effectiveness in both the operating system and application software at the same time. It is free and open-source software (FOSS) released under a GNU Lesser General Public License (LGPL).