Candlesticks are clearer to read in terms of price action compared to other types of charts. By observing the body and the color of the candlesticks you can determine the sentiment to be bullish or bearish. Also, a combination of two or three candlesticks form a pattern, which in turn gives the sentiment of the market.
You can use different timeframes for observing the sentiment in the market using candlesticks. However, higher timeframes tend to give more stable signals. A candlestick with a green body is bullish, which means that the bulls are in control. A candlestick with a red body is bearish.
A candlestick with no body or little body is called a doji candlestick. It represents indecision in the market. Do not use candlesticks alone to make trading decisions. Use technical analysis and fundamental analysis for additional confirmation.