DefinitionBasically, the Fourier series is a mathematical tool designed, in this case, for representing periodic functions as a weighted sum of elementary sine and cosine functions. There are several applications in signal processing, engineering, physics, and mathematics. This works for example to analyse/synthesise complex periodic phenomena like sound waves or electrical signals. Applications of the Fourier series include solving partial differential equations, data compression and image processing. For example, in electrical engineering, using the Aluminum series to analyze alternating current circuits and design filters to remove unwanted frequency components.