There are several ways to describe soil. Understanding these characteristics of soil helps the gardener amend soil.
Urban soil is often quite different from the native soil.
The native soil may have been compacted by heavy equipment and traffic. Subsoil excavated from basements is often dumped on the surface. Soil texture affects the water-holding capacity of soil, movement of water through the soil and ease of cultivation. Sand is visible, silt particles are the size of talc and clay particles are microscopic. Soils that are coarsely textured are sandy.