Beach
A beach is a small section of sand and black sand adjacent to standing water, such as an ocean.
Although any sand on the surface of the world can be considered desert, a proper beach exists because the sand was generated as part of placing the water when the world was initialized. This appears to take the shape of a large, rounded intrusion of sand into the previously existing dirt and stone which is then partially replaced by the slightly smaller body of water, leaving a border of sand. One common characteristic of a beach is underlying dirt.
Golden chests can commonly be found under beaches.
If the water is shallow enough, a deep bed of sand can underlie it. Otherwise, the water can run past the sand and onto stone and dirt below.
Flora
Fauna
You may find scorpions near the beach, maybe spawned next to a cactus