1. Rivers

2. Stream bed A stream bed is the channel bottom of a stream, river or creek; the physical confine of the normal water flow. As a general rule, the bed is that part of the channel, just at the "normal" water line and the banks are that part above the water line.

3. Stream bed of the Yukon river

4. Rate of water flow Rate of water flow, is the volume of water which passes through a given cross- section of the river channel per unit time. It is typically measured in cubic meters per second 1 m³/s.

5. Rate of water flow of the River Severn

6. The Amazon

7. Source of a river The source of a river is the place from which the water in the river or stream originates. The source of the Amazon river

8. Waterfall A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.

9. Waterfalls Angel Falls in Venezuela is the world's tallest waterfall at 979 m (3,212 ft).

10. Waterfalls Victoria falls Niagara falls

11. Waterfall animation http://www.cleo.net.uk/resources/displayfr ame.php?src=307/consultants_resources %2F_files%2Fgorge.swfhttp://www.cleo.net.uk/resources/displayfr ame.php?src=307/consultants_resources %2F_files%2Fgorge.swf

12. Rapid A rapid is a section of a river where the river bed has a relatively steep gradient causing an increase in water velocity and turbulence. A rapid is characterised by the river becoming shallower and having some rocks exposed above the flow surface.

13. Niagara rapidsRhine rapids

14. Floodplain A floodplain, or flood plain, is flat or nearly flat land adjacent to a stream or river that experiences occasional or periodic flooding. The Mississippi Flood Plain

15. Terrace Stream terraces are relict features, such as floodplains, from periods when a stream was flowing at a higher elevation and has downcut to a lower elevation.

16. Meanders http://www.cleo.net.uk/resources/displayfr ame.php?src=309/consultants_resources %2F_files%2Fmeander4.swfhttp://www.cleo.net.uk/resources/displayfr ame.php?src=309/consultants_resources %2F_files%2Fmeander4.swf http://www.wiley.com/college/strahler/0471 480533/animations/ch17_animations/anim ation1.htmlhttp://www.wiley.com/college/strahler/0471 480533/animations/ch17_animations/anim ation1.html

17. Mouth of a river The mouth of a river is the place where the river flows into another body of water. Mouth of the Amazon River

18. Delta Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river. The Nile River Delta

19. Watershed and drainage basin A watershed is the line separating neighbouring drainage basins (catchments). A drainage basin is an extent of land where water from rain or snow melt drains downhill into a river

20. The Amazon drainage basin

21. Main European drainage divides (red lines) separating drainage basins (gray regions)

22. Tributary A tributary is a stream or river which flows into a mainstream (or parent) river 'Right tributary' and 'left tributary' are terms stating the relative positions of the tributary to the mainstream river. These terms are applied from the perspective of looking downstream (in the direction the current of the water is going).