What is soil water
Outside United States irrigation and water management
Soil is not one big solid block. It is made up of many inorganic particles made up of clay, silt, sand, and rock, listed smallest particles to largest. There are spaces between these particles. The spaces are called pores. These pores are where we find the water and air in the soil.
Further explanation can be found at many on line resources under the topic of soil make up or water holding capacity. A pretty good description is at a page called Basic Soil Components.