Technical trading refers to trading using technical analysis techniques and tools (Trend following indicators, stochastic oscillators, Elliot waves, Fibonacci...)
The theory behind technical analysis is that historical prices and volume can be used to predict future price movements in a stock or an asset. Technical analysts or chartists believe that history can repeat itself and that technical trading can be used to detect these patterns and trade them profitably.
Technical trading is very popular and is widely used by traders for several reasons. One of these reasons is that technical trading does not require a lot of data, unlike fundamental trading.