Dow Theory (Dow Jones Theory) is a trading approach developed by Charles Dow.
Dow Theory is the basis of technical analysis of financial markets. The basic idea of Dow Theory is that market price action reflects all available information and the market price movement.
As per down theory if there is a Higher bottom -> higher top sequence along with a high volume then it is buy or long signal.
if there is a lower top -> lower bottom sequence along with a high volume then it is a sell or short signal.
The trend is reliable for a short period of 2-3 months.