A pier is a raised, often pile-supported structure projecting from shore into a waterway, providing above-water access for mooring boats, fishing, or cargo handling. Unlike solid quays, piers allow water to flow underneath. In American English, the term is sometimes used interchangeably with "dock" or "wharf".

Key Aspects of a Pier:
Purpose: Primarily used for docking vessels, loading/unloading passengers and cargo, and recreational activities like fishing.

Structure: Usually narrow and built on piles or pillars, which allows currents and tides to flow around it, minimizing silt buildup.

Mooring Types: Vessels may tie up along the side, or in a Mediterranean (Med) mooring style, where the stern is tied perpendicular to the pier with anchors set forward.

Distinction: While often used interchangeably with "dock," a pier specifically refers to the structure itself.