Overview
A doji is a candle where the open price is equal to (or nearly so) the close price. It is similar to a hammer.
Interpretation
A doji is very similar to a hammer, and the interpretation is nearly the same. The doji indicates indecision in the market, and because the open and closing price are the same, neither the bulls or the bears won the day, indicating more indecision than what may be interpreted in a hammer.
Neutral Doji
The neutral doji indicates equal strength between bulls and bears.
Dragonfly Doji
The Dragonfly doji, when seen during a down trend is thought to signal a possible reversal.
Gravestone Doji
The Gravestone doji, when seen during an up trend is thought to signal a possible reversal.