The term "wearables" is used to cover a broad range of tech products worn on the body, namely smartwatches, fitness trackers, and other devices like Google Glass. Wearables typically have a variety of sensors like an accelerometer or gyroscope to track things like movement, acceleration and heart rate. Most wearables connect to an external device in order to sync and/or receive data. A smartwatch for example would connect to a phone via Bluetooth in order to receive notifications or perform voice commands. A fitness band may connect to a PC via USB in order to send tracking results to a web server for viewing.