During the mid- to late 20th century, hearing aids that were carried in pockets were replaced by a more inconspicuous sort of model in which small zinc-air batteries were placed in the inserted unit itself. Cutting-edge technology allows for hearing aids so small and stylish they can be mistaken for wireless headsets.

In the past, a funnel-like amplification cone, called an "ear trumpet" or "ear horn" was used. Also sometimes used was a desk with a built-in amplifier into which a microphone and earphones could be plugged; these worked better than passive ear trumpets but were not portable.

That loss of the ear's 'fine-tuning' (called ski slope loss) causes a lot of people to have difficulty hearing if there is any kind of background noise. It's the most common form of hearing problem, especially with those over 55. It's not 'deafness' in the accepted sense, but certainly a hearing aid would help with the problem.

The pinna may be all that shows of the ear, but it has only a tiny role in hearing and none at all in the sense of balance. In people, the pinna is more often called the auricle. Vertebrates have a pair of ears, each one placed symmetrically on opposite sides of the head. That arrangement aids in the ability to balance and in the ability to localize sound.