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 variety of USB cables, including micro-USB, mini-USB, and standard USB. USB cables are used to connect devices -- such as printers, keyboards and music players -- to computers.USB cables allow computers to connect to peripheral devices. variety of USB cables, including micro-USB, mini-USB, and standard USB. USB cables are used to connect devices -- such as printers, keyboards and music players -- to computers.