The Dow Theory is one of the most popularly used concepts of charting & Technical Analysis. It happens to be one of the oldest technical analysis tools as well. Dow Theory days back to as early as 1900 to 1902 when Charles Dow laid the basic principles. The Theory named after him as Dow Theory. It helps investors in the stock market to understand the health of the trade condition. The father of Dow Theory, Mr. Charles Dow died in 1902 but after his death work of Dow Theory was continued by William Hamilton.