Conductor with oscillating driving voltage and currents will radiate like an antenna. By providing a shield, we can minimize radiation as shield carries current in the opposite direction. This constitutes a transmission line structure where voltage and current on the line obey wave equation. Using a solution to this equation, we can develop an effective impedance seen at the source from a load at the other end. We develop the concept of reflected wave and show how reflected waves hinder efficient power transfer and can be avoided by impedance matching a line.