Depositional landforms formed by action of waves and currents.

In the context of geomorphology, bars, barriers, and spits are depositional landforms formed by the action of waves and currents. These landforms are commonly found along coastlines and in river systems where the interaction of water and sediment creates dynamic and ever-changing features.

1. Bars:
- Bars are long, narrow deposits of sand or other sediment that are parallel to the shoreline.
- They are formed when waves and currents transport sediment along the coast and deposit it in shallow water areas.
- Bars can be submerged or emerge above the water surface depending on the tides and wave conditions.
- They play an important role in coastal processes, acting as natural buffers against erosion and providing habitat for various marine organisms.

2. Barriers:
- Barriers are similar to bars but are more extensive and usually form near the coast.
- They are elongated ridges of sand or gravel that run parallel to the shore and are separated from the mainland by a lagoon or marsh.
- Barriers are created by the deposition of sediment by longshore drift, where waves and currents move sediment along the coast.
- They provide protection to the mainland by acting as a barrier against storm surges and wave action.
- Barrier islands, such as those found along the Atlantic and Gulf coasts of the United States, are examples of this landform.

3. Spits:
- Spits are elongated ridges of sand or gravel that extend from the mainland into a body of water.
- They are formed by the deposition of sediment carried by longshore drift and then shaped by wave and current action.
- Spits often have a curved or hook-shaped end, known as a recurved spit, which is influenced by the direction of the prevailing winds and currents.
- They are typically found at the mouths of rivers or in sheltered bays.
- Spits can change in shape and size over time as sediment is eroded and deposited by the forces of wind and water.

Overall, bars, barriers, and spits are all depositional landforms that result from the action of waves and currents. They play important roles in coastal processes, providing protection against erosion, creating diverse habitats, and shaping the morphology of coastal landscapes.