A pattern is recognized by a line linking common price points, such as closing prices, highs, and lows, throughout a specified time period.
Technical analysts attempt to uncover patterns to forecast the future price movement of a security.
These patterns can range in complexity from trendlines to double head-and-shoulders formations.

During an uptrend, the formation of a reversal chart pattern indicates that the trend will soon reverse and the price will decline.
In contrast, the presence of a reversal chart pattern during a downtrend indicates that the price will eventually rise.

Typically, these patterns are also referred to as consolidation patterns, as they illustrate how buyers or sellers take a brief pause before continuing in the same direction as the prior trend.
Generally, trends do not go in a straight line up or down. They pause and move sideways, then "correct" lower or upward before regaining momentum and continuing the main trend.