The bottom rear part of a shoe is the heel. These come in a variety of sizes and are usually made to support the large stresses applied to the heel of the foot. They are often made of the same material as the sole of the shoe:

Low heel: is considered less than 1".

Mid heels: are considered from 1" to 2.5".

High heel: is anything over 2.5". High-heels come in a wide variety of styles, and the heels are found in many different shapes, including stiletto, block, tapered, blade, and wedge.