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 flash drive is a compact, rewritable, data storage device that connects to a computer through a Universal Serial Bus (USB) interface. These drives can be as small as 128 MB, and as large as 256 GB, and researchers are even looking at ways to increase that capacity up to 2 TB.