A cochlear implant is a small, complex electronic device that can help provide a sense of sound to a person who is profoundly deaf or severely hard-of-hearing. The implant consists of an external portion that sits behind the ear and a second portion that is surgically placed under the skin. An implant has a microphone, which picks up sound from the environment. Then a speech processor selects and arranges the sounds picked up by the microphone. A transmitter and receiver/stimulator receive the signal from the speech processor and convert it into electric impulses. An electrode array, which is a group of electrodes, collects the impulses from the stimulator and sends them to different regions of the auditory nerve. An implant does not restore normal hearing. Instead, it can give a deaf person a useful representation of sounds in the environment and help him or her understand speech.