A plain is a broad area of relatively flat land and is one of the major landforms on the earth surface. There are various types of Plains which are discussed as:
Structural plains: relatively undisturbed horizontal surfaces of the earth. They are structurally depressed areas of the world that make up some of the most extensive natural lowlands on the Earth’s surface.
Erosional plains that have been leveled by various agents of denudation such as running water, rivers, wind and glacier which wear out the rugged surface and smoothens them. Plain resulting from the action of these agents of denudation are called peneplains(almost plain) while plains formed from wind action are called pediplains.
Depositional Plains: formed by the deposition of materials brought by various agents of transportation such as rivers, wind, waves, and glaciers. Their fertility and economic relevance depend greatly on the types of sediments that are laid down.
Glacial plains, formed by the movement of glaciers under the force of gravity
Abyssal plain, a flat or very gently sloping area of the deep ocean basin.