The information is an indirect existence world, which is different from the direct existence matter world. The knowledge is a systematized information assemblage formed by cognitive subject’s perception and information process and creation of thought; the intelligence is active modes and methods that subjects with cognition and practice abilities grasp, manage, create, exploit, utilize and realize information (including knowledge); the practice is not an activity of pure materiality but a process of realizing subjects’ intentionality information in the objects through implementing planning information.In the human activities, information, knowledge, intelligence and practice have a property of holographic unification.