Forex charts are available in different time frames. For MT4, the standard time frames available include M1 (1 Minute), M5, M15, M30, H1 (1 Hour), H4, D1 (1 Day, W1 (1 Week), and MN (1 Month). A candle in each higher time frame can be though of as a combination of the candles in a lower time frame. For example, take the 60 1 minute candles from 2:00 pm until 2:59 pm, combine the data, and you'll have the 2 PM hourly candle. Each time frame can have it's own trends. Moving to smaller timeframes is sometimes considered to be "zooming in" and moving to larger timeframes is sometimes thought of as zooming out. Many traders will trade a specific time frame, but will check one or two timeframes down for trend changes and one or two timeframes up to see the "bigger picture".