The double top pattern is a key technical indicator used to signal the potential end of an uptrend and the start of a downtrend. It forms when the price reaches a high point, pulls back, rises again to the same level, and then begins to decline. This pattern suggests that the buyers' momentum has been exhausted and that sellers are taking control, pushing the price lower. Traders view the double top as a strong indication that the asset's price will likely continue downward.