In recent years, there has been a major surge of interest in the development of simulation techniques and strategies for fluid-structure interaction (FSI) problems, mainly driven by a large spectrum of applications in physiology, medical sciences, material sciences, manufacturing processes, and many other engineering disciplines. Numerous methodologies have been proposed to more accurately and more efficiently capture the coupled interactions between fluid and structures. There are several different ways to classify FSI modeling, for example, monolithic and partitioned, or conforming and nonconforming meshes. Along the line of conforming and non-conforming classification, Arbitrary Lagrangian Eulerian (ALE) method is a typical example of conforming mesh; while the immersed methods, e.g. immersed boundary method, immersed finite element method, are good examples of non-conforming meshes. There are advantages and disadvantages for each chosen approach. The computational mathematics and mechanics communities have been working together in search for the optimal strategies.