There is a way of viewing a thing (say, a dog) as a physical entity. There is another way where the dog is simply some kind of transformation on bits in -> bits out. The bits in are the dogs sensory input and the bits out are your own sensory input (smell, touch, sight, thought). You then mutate those bits and generate bits out for everyone else.

The world is maybe not physical but made up of information. So everything is simply a processor of information. You might call this software.

Corollary: nothing discretely exists but mappings (functions). The source code of the universe is functional programming, not OOP.