While a large number of simultaneous new highs and new lows is indicative of some amount of internal dispersion across individual stocks, this situation often occurs in markets that have been somewhat range-bound.

Still, when we think of market "internals," the number of new highs and new lows can contribute useful information. To expand on the vocabulary we use to talk about internals, "leadership" typically refers to the number of stocks achieving new highs and new lows; "breadth" typically refers to the number of stocks advancing versus declining in a given day or week; and "participation" typically refers to the percentage of stocks that are advancing or declining in tandem with the major indices.

The original basis for the Hindenburg signal traces back to the "high-low logic index" that Norm Fosback created in the 1970's. Jim Miekka introduced the Hindenburg as a daily rather than weekly measure, Kennedy Gammage gave it the ominous name, and Peter Eliades later added several criteria to reduce the noise of one-off signals, requiring additional confirmation that amounts to a requirement that more than one signal must emerge in the context of an advancing market with weakening breadth.