A hearing device could be a hearing aid or personal sound amplifier (PSAP) or an assisted listening device.  These are all different but with the same goal in mind - to help you hear better. A hearing aid is a small electronic device that you wear in or behind your ear.  Hearing Aids are programmable - that means you first take a hearing test, The ENT charts your hearing loss on an audiogram.  This audiogram is used to program your hearing aid.   Hearing Aids are prescribed for the mild, moderate, severe to profound hearing loss. Personal Sound Amplifiers (PSAPs) are almost the same thing as hearing aid  - PSAPs are small electronic hearing device that you wear in or behind your ear.  PSAPs are ready to wear, are over-the-counter electronic hearing devices (they are not FDA approved medical devices like hearing aids) that come in many different shapes and sizes but PSAPs will look identical to hearing aids.  They are essentially Indistinguishable from hearing aids.  They have almost the same technology inside except they are not programmable.  Most come with manual volume control.   It's also important to know that PSAPs work best for people with mild to moderate hearing impairment, if you have severe hearing loss-its not going to help to much.   You don't need a prescription to buy them, and they usually aren't covered by insurance or Medicare. Assisted Listening Hearing Devices are amplifiers that bring sound directly into the ear.  They separate the sounds, particularly speech, that a person wants to hear from background noise.  They improve what is known as the “speech to noise ratio.” Assisted Listening Devices utilize FM, infrared, or inductive loop technologies. FM systems are ALSs that use radio broadcast technology.  They are often used in educational settings and offer mobility and flexibility when used with portable body-worn transmitters.  Some newer FM systems utilize miniaturized receivers that fit onto a hearing aid via a “boot.” Infrared systems are ALSs that utilize light-based technology.  They guarantee privacy because light does not pass through walls.  They are the appropriate choice for situations such as court proceedings that require confidentiality.  They are frequently installed in places of entertainment.  They are also frequently designed and marketed for use in television listening.  See below Wide area loop systems utilize an electromagnetic field to deliver sound.  They offer convenience to groups of t-coil hearing aid users because those users do not require body worn receivers.  Loop systems can be used by non-hearing aid users through use of a headphone and inductive loop receiver. Assisted Listening devices could also be Phones with screens where you can read the captions or conversation.