The proposition that information is physical is widely accepted in the scientific community. Information is composed of physical representation, abstract meaning and rules, which interpret representation to meaning. In this article, I demonstrated that the rules connecting representation with meaning cannot be the laws of physics, because all quantities appearing in the laws of physics are physical, observable and measurable, and the meaning, however, is abstract, unobservable and unmeasurable. For linguistic information, the rules that determine how the ordered symbol sequence of language corresponds to its meaning are language vocabulary and grammar, not the laws of physics. This characteristic of information – its rules that link representation with meaning do not obey the laws of physics – ontologically distinguishes information from physical substances that obey the laws of physics, and inspires me to define entities that do not obey the laws of physics (such as information) as non-physical.