Laplace operator (or Laplace operator) and Laplace transform are two methods to deal with functions, one is differentiation and the other is integration. The specific form is not written. You can refer to Gu Qiao's Mathematical Method and Liang's Mathematical Method. Laplace transform is mainly used in signals and systems. These two methods have different starting points and purposes for function processing. Laplace operator is produced in the process of dealing with divergence and curl of function, and Laplace equation and Poisson equation are commonly used. The integral form is introduced in the process of dealing with the function problem that does not meet the Fourier transform condition, and its purpose is to observe a function from different angles or domains.