# 4: Hyperbolic Equations

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Here we consider hyperbolic equations of second order, mainly wave equations.

Thumbnail: A solution to the 2D wave equation. (CC-SA-By-4.0; BrentHFoster). The wave equation is an important second-order linear partial differential equation for the description of waves, such as sound waves, light waves and water waves. It arises in fields like acoustics, electromagnetics, and fluid dynamics.