How Do You Measure A Waterfall’s Height?

One of the most often-reported parameters about a waterfall is its height. How often do you see brochures or websites reporting that Angel Falls is the tallest waterfall in the world at 898m (3,292ft), or some waterfall is X times taller than Niagara Falls, or Yosemite Falls is one of North America’s tallest at 2,425ft, etc. etc.? Indeed, what is it about a waterfall’s height that grabs our attention so much?