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 USB Type A plug. The Universal Serial Bus (USB) is technology that allows a person to connect an electronic device to a computer. It is a fast serial bus. It is mostly used on personal computers. USB is also used on other devices, such as the PlayStation 3, PlayStation 4, the Xbox 360, and others. USB connects different devices using a standard interface.