Jargon busters: MP3 player accessories3.5mm jack (or headphone jack): The standard and most popular connector for headphones.
Alkaline batteries: A type of power cell often used to power small electronic devices, such as portable speaker systems. Some alkaline batteries are designed to be recharged.
Armband: A style of MP3 or iPod case that is worn around the arm, usually with the aid of a Velcro strap. Armband cases are popular with exercisers and are ideal for use in the gym.
Around-the-ear: A type of headphone that wraps around the ear, creating a better fit. Around-the-ear headphones are ideal for exercising or similar physical activity.
Bass: A lower register of pitch in music. Many speaker systems allow the adjustment of bass levels to provide a variation in sound.
FM transmitter: A small device that allows you to wirelessly stream music from your iPod or MP3 player to your car stereo via FM transmission, the same technology used to deliver radio in your car.
IEMs: In-ear-monitors. A type of headphone that rests inside your ear canal rather than on top of it. IEMs can often be uncomfortable for first-time users, but generally provide excellent sound quality and reduce external noise.
iPod connector: A 30-pin dock connector that allows iPods to be connected to a variety of accessories, including speaker systems. The iPod connector is a proprietary Apple interface.
Over-the-ear: A type of headphone that sits over the entire ear, sealing it in an attempt to prevent ambient noise. Over-the-ear headphones often have poor sound leakage, meaning those around you will be able to hear your music, even at moderate volumes.
Silicone: A rubber-like material that is used on many basic iPod or MP3 player cases. A silicone case will stretch slightly to fit around a player and will protect from scratches, though its rubbery feel can often make it hard to pull out of your pocket.
Splitter: An accessory that can allow multiple people to simultaneously listen to your music through headphones.