The price bar summarises the real-money transactions in a security during a day. Here are a few rules of thumb on how to interpret it: the close is the most important of the four data points up days are bullish, down days are bearish (duh) close at the high is especially bullish, close at the low especially bearish open at the high is bearish, open at the low is bullish a series of higher highs is bullish, lower lows are bearish - this is the definition of a trend