A Channel is formed when we draw a trendline and then a line parallel to the trendline with most of the price action if not all falling between the two lines. By scanning through a few charts, you will find that it is easy to identify channels. Channels occur frequently.
However, currencies rarely stay in a narrow range for long and have a tendency to breakout from a tight range and develop a strong trend in the market. Important economic news releases can act as a trigger for a breakout.