Foundation (engineering)
A foundation is the element of a structure which connects it to the ground, and transfers loads from the structure to the ground. Foundations are generally considered either shallow or deep. Foundation engineering is the application of soil mechanics and rock mechanics (Geotechnical engineering) in the design of foundation elements of structures.
Post in ground
Post in ground construction, also called earthfast or hole-set posts, is a type of construction in which vertical, roof-bearing timbers, called posts, are in direct contact with the ground. They may be placed into excavated post holes, driven into the ground, or on sills which are set on the ground without a foundation. Earthfast construction is common from the Neolithic period to the present and is used worldwide. Post-in-the-ground construction is sometimes called an "impermanent" form such as for houses which are expected to last a decade or two before a better quality structure can be built.