Sometimes referred to as earphones, headphones are a hardware output device that either plug into your computer line out or your speakers. Headphones allow you to listen to audio or watch a movie without disturbing people around you. The picture is an example of a USB headset from Logitech, which also include a microphone (an input device), a popular solution for computer gaming.
Note: If you have speakers connected to your computer, connecting headphones to the line out or headphones connection will result in sound only being output to the headphones. To have the sound output for headphones and speakers, you will need to use USB headphones.
The first pair of audio headphones were invented by Nathaniel Baldwin in 1910. The U.S. Navy ordered 100 pairs of those first headphones because they recognized the potential advantages, despite many people being skeptical about their usefulness.
Headphones come in several shapes and styles. The more traditional style of headphones looks similar to headphones shown above. These types of headphones have styrofoam or another soft fabric around the earpieces to provide comfort around your ear, and a plastic or light metal band between each earpiece. The band fits over your head and helps to keep the headphones from moving around or sliding off your head and ears.
The most basic type of headphones, earbuds, are small, and fit in your ear. They are usually shaped in a specific way as to fit comfortably in your ear. Some earbuds come with several sets of different sized rubber inserts that fit over the earbuds. Depending on the size of the user's ears, they can choose the size of rubber insert that best fits their ear canal. The picture to the right is an example set of earbuds.