Technical Analysis of the Financial Markets by John J. Murphy

Should I use technical analysis or fundamental analysis?

Fundamental analysis (earnings, revenue, valuation) works best for long-term investing and swing trading. Technical analysis (charts, patterns, indicators) works best for timing entries/exits and short-term trades. Most successful traders use both — fundamentals to pick what to trade, technicals to decide when. Pure technical analysis without understanding the underlying business is gambling with chart decorations.