I don't understand EM Theory. Help me.

There is a great deal of reading you need to do to help you understand Maxwell's Theory:

The first one listed below is an essay titled "Why is Maxwell's Theory So Hard to Understand".

http://www.sonnetusa.com/news/DMLfiles/dysonessay.pdf

Maxwell Theory (http://www-ssc.igpp.ucla.edu/personnel/russell/papers/max_mag/)

Maxwell’s Equations and Electromagnetic Waves (http://galileo.phys.virginia.edu/classes/109N/more_stuff/Maxwell_Eq.html)

Maxwell's equations - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Electromagnetic_theory)

Electromagnetism - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Electromagnetism)