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The main processes involved in rivers are:

• Erosion - the wearing away of the land and the stones carried in the river.
• Transport - the movement of rocks, sand, and silt by the river.
• Deposition - the dumping of rocks, sand and silt wherever the river slows down.

Erosion

The main ways in which a river erodes are:

• Corrasion - wearing away of the river bed and banks by the load hitting against them.
• Attrition - wearing down of the load as the rocks and pebbles hit the river bed and each other, breaking into smaller and more rounded pieces.
• Hydraulic action - breaking away of the river bed and banks by the sheer force of the water getting into small cracks.
• Chemical action (corrosion) - water dissolves minerals from the rocks and washes them away.

Transport

The main ways in which transport happens are:

• Traction - quite large stones can be rolled or dragged along the river bed by the force of the water.
• Saltation - small stones, which the water cannot lift, bounce off each other and are carried forward for short distances by the water above the river bed.
• Suspension - if particles are small enough the river can lift them and carry them long distances.
• Solution - when the river dissolves minerals from the rocks they are carried in the water itself.

Deposition

The main way in which deposition happens is:

• Loss of Speed - when the river slows down on the inside of bends or when it meets deeper water, like a lake, it loses energy and cannot carry so much, so drops some of its load.