In his 1809 onomatopoeia the British poet Southey used words to imitate the various natural sonances of falling water. These and other explosive variations among waterfalls do have their commonalities, however. The generic elements are running water and rock and their powerful clash. Effect of the water and rock types of varying resistance through eons of time essentially creates waterfall and their differences. The creation and differences begin almost simultaneously with erosion.
Bedrock is exposed and the drop of a stream is broken by ribbons of harder rock that form cataracts.
The evolution of waterfalls is exemplified by Linville Falls near Spruce Pine. Prior to the turn of the century Linville was a set of two falls with the upper and lower sections equally high at 35 feet. Between 1895 and 1902, flood waters caused a ledge of the upper section to give way resulting in the upper falls now only dropping 20 feet while the lower has increased to 45. This has changed Linville Falls' configuration drastically. Few question the comparison.