When the price of the beginning of period is lower during the end of period, it means that the prices increased and the candle is green. In that case, the stocking of the candle represents the price of the beginning of period, whereas the top represents the course(price) to the term of period. The superior "drill"represents the highest price reachedduring period, conversely for the low drill.
Now you know how to read a graph. But it is also necessary you to learn to use them, and it is moreover the most fundamental point in your apprenticeship of Forex.