A shifting foundation can cause problems like misaligned doors and windows that stick or don't open and close properly and pressure from soil on the foundation can cause leaning or bowing walls. When you finally do decide to fix the foundation, it won't magically fix these problems.
A pier foundation is a collection of large diameter cylindrical columns to support the superstructure and transfer large super-imposed loads to the firm strata below. It stood several feet above the ground. It is also known as “post foundation”. Here are adjustable steel piers in a crawl space.