Any retaining wall type that is a) driven or pushed into the ground rather than poured or injected, and b) has a relatively thin cross-section and low weight so that the weight of the wall does not contribute to the wall's stability is referred to as a sheet pile.

The contemporary sheet piling industry has existed for a little over a century, with the type and variety of products having seen possibly their most significant alterations since the early 1970s. In many different applications, sheet piling has been used, particularly in marine bulkheads and retaining walls where space is at a premium. The cellular cofferdam is a specific kind of retaining wall in addition to these that is widely utilized for both temporary and permanent projects.

Similar to Z piles, U sheet piles retain soil and water, but with one crucial distinction: U piles have the interlock on the neutral axis. Due to shear transfer issues, placing the lock in the center of the wall diminishes the section's efficiency and may result in a reduction in the section's characteristics.