A heel is the bottom, back part of a shoe or boot that provides elevation. The styling and construction of a heel may vary (i.e., stacked, stilletto, spiked, sculptured, kitten).
About Strappy Sandals:
Strappy Sandals are sandals that are characterized by multiple straps covering the toe and/or heel. The straps on strappy sandals can be used to secure the shoe to the foot or some of them may be more for ornamentation.