DOW theory is the basic theory to find the demand and supply trend of the stock. It need to find the TOP and BOTTOM of the trend and qualify them. HB to HT trend are Bullish and LT to LB trend are Bearish. DOW theory is not for sell/buy stocks. Its to find the Demand and Supply of the stock price. Its for Long term and not for intraday trading. Support is the price point where buyers can be expected more than Sellers.Resistance is the price point where Sellers can be expected more than Buyers.