Many people believe that the markets are random. In fact, one of the most prominent investing books out there is "A Random Walk Down Wall Street" (1973) by Burton G. Malkiel, who argues that throwing darts at a dartboard is likely to yield results similar to those achieved by a fund manager (and Malkiel does have many valid points). 
 
However, many others argue that although prices may appear to be random, they do in fact follow a pattern in the form of trends. One of the most basic ways in which traders can determine such trends is through the use of fractals. Fractals essentially break down larger trends into extremely simple and predictable reversal patterns.

What Are Fractals?

When many people think of fractals in the mathematical sense, they think of chaos theory and abstract mathematics. While these concepts do apply to the market (it being a nonlinear, dynamic system), most traders refer to fractals in a more literal sense. That is, as recurring patterns that can predict reversals among larger, more chaotic price movements.

Here are a few things to remember when using fractals:

They are lagging indicators. They are best used as confirmation indicators to help confirm that a reversal did take place. Real-time tops and bottoms can be surmised with other techniques.
The longer the time period (i.e. the number of bars required for a fractal), the more reliable the reversal. However, you should also remember that the longer the time period, the lower the number of signals generated.

It is best to plot fractals in multiple time frames and use them in conjunction with one another. For example, only trade short-term fractals in the direction of the long-term ones. Along these same lines, long-term fractals are more reliable than short-term fractals.