The spectral element method is a high-order numerical technique used for solving partial differential equations (PDEs). It combines the spectral accuracy of spectral methods with the flexibility and local refinement capabilities of finite element methods. In the spectral element method, the computational domain is divided into a mesh of elements, typically triangles or quadrilaterals in two dimensions or tetrahedra or hexahedra in three dimensions. Within each element, high-order polynomial interpolants are used to approximate the solution. The method is spectrally accurate, meaning that it can achieve very high levels of accuracy with relatively few degrees of freedom by using high-degree polynomials within each element. One of the main advantages of the spectral element method is its ability to handle complex geometries and adaptively refine the mesh in regions of interest, leading to efficient and accurate simulations. It is commonly used in a wide range of applications, including fluid dynamics, solid mechanics, and electromagnetics.