1 Echocardiography (echo) is a painless test that uses sound waves to create pictures of your heart.  This test gives your doctor information about the size and shape of your heart and how well your heart's chambers and valves are working.
USB was designed to standardize the connection of computer peripherals (including keyboards, pointing devices, digital cameras, printers, portable media players, disk drives and network adapters) to personal computers, both to communicate and to supply electric power.
A universal serial bus, or USB, device refers to any device that utilizes USB connections to connect to a computer. Common examples include external hard drives, webcams, printers, scanners, digital cameras, keyboards and mice. The USB connection symbol is usually denoted on the connector. Continue Reading.