Ear canal in the context of "Earwax"

Headphones are a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an audio source privately, in contrast to a loudspeaker, which emits sound into the open air for anyone nearby to hear. Headphones are also known as earphones or, colloquially, cans. Circumaural (around the ear) and supra-aural (over the ear) headphones use a band over the top of the head to hold the drivers in place. Another type, known as earbuds or earpieces, consists of individual units that plug into the user's ear canal; within that category have been developed cordless air buds using wireless technology. A third type are bone conduction headphones, which typically wrap around the back of the head and rest in front of the ear canal, leaving the ear canal open. In the context of telecommunication, a headset is a combination of a headphone and microphone.

Headphones connect to a signal source such as an audio amplifier, radio, CD player, portable media player, mobile phone, video game console, or electronic musical instrument, either directly using a cord, or using wireless technology such as Bluetooth, DECT or FM radio. The first headphones were developed in the late 19th century for use by switchboard operators, to keep their hands free. Initially, the audio quality was mediocre and a step forward was the invention of high fidelity headphones.

In vertebrates, an ear is the organ that enables hearing and (in mammals) body balance using the vestibular system. In humans, the ear is described as having three parts: the outer ear, the middle ear and the inner ear. The outer ear consists of the auricle and the ear canal. Since the outer ear is the only visible portion of the ear, the word "ear" often refers to the external part (auricle) alone. The middle ear includes the tympanic cavity and the three ossicles. The inner ear sits in the bony labyrinth, and contains structures which are key to several senses: the semicircular canals, which enable balance and eye tracking when moving; the utricle and saccule, which enable balance when stationary; and the cochlea, which enables hearing. The ear canal is cleaned via earwax, which naturally migrates to the auricle.

The ear develops from the first pharyngeal pouch and six small swellings that develop in the early embryo called otic placodes, which are derived from the ectoderm.

Ear hair is the terminal hair arising from follicular cartilage inside the external auditory meatus in humans. In its broader sense, ear hair may also include the fine vellus hair covering much of the ear, particularly at the prominent parts of the anterior ear, or even the abnormal hair growth as seen in hypertrichosis and hirsutism. Medical research on the function of ear hair is currently very scarce.

Hair growth within the ear canal is often observed to increase in older men, together with increased growth of nasal hair. Visible hair that protrudes from the ear canal is sometimes trimmed for cosmetic reasons. Excessive hair growth within or on the ear is known medically as auricular hypertrichosis. Some men, particularly in the male population of India, have coarse hair growth along the lower portion of the helix, a condition referred to as "having hairy pinnae" (hypertrichosis lanuginosa acquisita).

The outer ear, external ear, or auris externa is the external part of the ear, which consists of the auricle (also pinna) and the ear canal. It gathers sound energy and focuses it on the eardrum (tympanic membrane).