Interference is a phenomenon that occurs when two or more waves converge and interact with one another.

When these waves intersect, they combine to form a new wave that may exhibit different characteristics, such as amplitude, frequency, and wavelength, compared to the original waves. The outcome of this interaction can either amplify or diminish the resultant wave, depending on the phase relationship of the interacting waves.

Constructive Interference occurs when the waves are in phase, meaning that their crests and troughs align perfectly. In this case, the amplitude of the resultant wave is greater than that of the individual waves. A classic example of this effect can be observed in the bright fringes of a double-slit experiment.

Conversely, Destructive Interference takes place when the waves are out of phase, meaning that their crests and troughs do not align. As a result, the amplitude of the resulting wave is diminished, leading to a wave with less intensity than the original waves. This phenomenon can be seen in the dark fringes of a double-slit experiment.

Interference can also occur between waves of different frequencies, creating what are known as beats. When two waves of slightly varying frequencies interfere, they produce a wave with an amplitude that fluctuates over time, which can be perceived as a pulsing or throbbing sound.

This phenomenon of interference is significant in various fields of physics, including optics, acoustics, and quantum mechanics. It has practical applications in technologies such as noise-cancelling headphones, holography, and interferometry.