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 device being inserted into a USB port. A USB device being inserted into a USB port. USB is defined as an acronym that stands for Universal Serial Bus which is a type of computer port which can be used to connect equipment to a computer. An example of a USB is the interface used to upload pictures from a digital camera to a computer.