Quantum theory and the theory of relativity, developed in the early 20th century, have further extended human knowledge of the universe we are living in, from the level of subatomic particles to galaxies. Many theories have become obsolete as new ones developed during the years. Maxwell's equations, however, amazingly remain the fundamental principle for macroscopic electromagnetic system analyses, and they are still being studied by researchers in different and wider application areas. Maxwell's equations are behind many of the technological innovations that changed the world during the past century, from early designs of electric power generators and the invention of radio broadcast, to the recent wireless communication boom and the information superhighway. Most applications of the electromagnetic theory have been focused on the deep understanding and analysis of the theory, especially getting meaningful solutions to practical electronic systems.