A wwaterfall is an area where water flows over a vertical drop or a series of steep drops in the course of a stream or river.
- Plunge: Water descends vertically, losing contact with the bedrock surface.
- Horsetail: Descending water maintains some contact with bedrock.
- Cataract: A large, powerful waterfall.
- Multi-step: A series of waterfalls one after another of roughly the same size each with its own sunken plunge pool.
- Block: Water descends from a relatively wide stream or river.
- Cascade: Water descends a series of rock steps.
- Segmented: Distinctly separate flows of water form as it descends.
- Tiered: Water drops in a series of distinct steps or falls.
- Punchbowl: Water descends in a constricted form and then spreads out in a wider pool.
- Fan: Water spreads horizontally as it descends while remaining in contact with bedrock.
- Ephemeral: They do not flow continuously.
A valley is a low area between hills or mountains typically with a river running through it.
- River Valley: Formed by the erosive action of water flowing over the land.
- Glacial Valley: Due to breadth and weight of glaciers, these valleys are wider and have flat bottoms with a contour similar to a "U"
- Flat-floored Valley: Most common type of valley in the world. Over time rivers and streams spread across the valley (either River or Glacial), persistently eroding its edges.
# Key Points
- The world's highest waterfalls are Angel Falls in venezuela (979m) and Tugela Falls in South Africa (948m).
- India's higghest waterfalls are Nohkalikai Falls (340m) and Meenmutty Falls(300m).