The human skeletal system comes packaged with 206 bones and three types of cartilage. Hyaline cartilage is found in the embryonic skeleton, fibrocartilage is found in the intervertebral disks, and elastic cartilage is found in the epiglottis, larynx, and the outer ear. As its name suggests, elastic cartilage is significantly more pliable than either hyaline or fibrocartilage. This is because it's comprised of elastic fibers and collagen.
This network of elasticity forms a solid matrix, protecting itself from rupture and similar fates. This matrix of fibers lends the part a significant flexibility, and this means it can withstand repeated instances of bending. To see a perfect example of elastic cartilage in action, try wiggling the little walls around your ear canal — they're both firm and flexible.
Of course, it would be irresponsible to assume it can withstand any sort of treatment; it is not only possible to damage it, but it can occur with a certain degree of ease. For example, if you were hit in the ear with a significant amount of force, the cartilage could break and leave the ear with a deformed appearance. This is often seen in baseball players and rugby players, both of whom have dubbed the condition "cauliflower ear." It isn't known exactly how many people in the world suffer from damaged elastic cartilage, though it is thought to be common.
Also known as yellow cartilage because of its yellowish appearance, elastic cartilage's main purpose is to provide support and a moderate amount of protection. On the outer ear, or the pinna, it surrounds part of the ear canal. This keeps the rest of the ear in place while offering some protection from foreign obstructions entering or damaging the ear.
In the windpipe, elastic cartilage functions with much more protection in mind. In the musculoskeletal system, every human has an esophagus, where food and oxygen both travel. At some point it sections off into two pipes: one is meant for air, the other is meant for food. The epiglottis is the cartilage flap that slides over the windpipe each time you swallow, so it protects you from accidentally breathing in your food.
Overall, like any other part in the musculoskeletal system, elastic cartilage plays an important part in protection, maintenance and development. Without it, the ears would look malformed. More significantly, food would often slip into your lungs, causing you to choke even while eating carefully.