Conceptual models

Entities

The 'entity' model is the most common model of world. The approach is based on the concept that space is populated with entities or objects. This sort of approach means that the entity is defined, its attributes are listed, and its boundaries and location defined.

Fields

The 'continuous fields' approach is the simplest model of the world. It represents geographical space in terms of continuous coordinates at two or three dimensions. The attribute is assumed to vary continuously and smoothly over space.