A cochlear implant is a small electronic device that can help provide a sense of sound to a person who is profoundly deaf or severely hard-of-hearing. It is designed to mimic the function of a healthy inner ear or cochlea. Unlike hearing aids, which amplify sound, a cochlear implant bypasses damaged portions of the ear and directly stimulates the auditory nerve. The implant consists of an external portion that sits behind the ear and a second portion that is surgically placed under the skin. The external portion includes a microphone, sound processor, and transmitter system, while the implanted portion contains the electronic circuits that receive signals from the external system and send electrical currents to the inner ear. Cochlear implants use electrodes that extend into the cochlea to stimulate the nerves that help with hearing. The signals generated by the implant are sent by way of the auditory nerve to the brain, which recognizes the signals as sound. Hearing through a cochlear implant is different from normal hearing and takes time to learn or relearn. The use of a cochlear implant requires both a surgical procedure and significant therapy to learn or relearn the sense of hearing. Cochlear implants are not suitable for everyone, and the decision to receive an implant should involve discussions with medical specialists, including an experienced cochlear-implant surgeon.