The Broglie equation just described the matter as wave in mathematical form, the electron in particular.
As homemadeclock told you, this character of an electron, the matter wave, is used in science to determine the propability of the location. A good example is the potential well in which the electron is moving from one wall of the well to another with an endless distance to each other. By this movement, the electron is causing a standing wave with antinodes and wave troughs. From propability's view the troughs means the impossibility to find an electron in the potential well at a certain point, while the antinodes in turn stand for the higest propability of finding this particle.