Technical indicators are algorithmic indicators meant for trading. These are only indicators for some direction and guidance. They are not meant to take decisions, but only supporting tools.
Analysis based on Dow, Price patterns are based on Demand & supply, can facilitate decisions.
No algorithm helps to support decisions in all the days.
Technical indicators are only supplemental to the TA based on price/volume analysis.
Two key technical indicators are Moving Averages and Fibonacci retracement