# What Is Space? Space is the collection of distances defined by ordered signal separation. A distance is a count of how many recurrent signal steps separate two configurations. Once such steps are ordered, they can also be described as causal steps. The total set of such separations forms the relational structure we call space. Geometry is descriptive. It summarizes the organization of flow. When the resulting distance relations can be represented coherently in three dimensions, we use that representation and call it space.