**5. Conclusions**

In this chapter, we first described a third order chaotic system with hyperbolic sine nonlinearity, then we introduced the method to expend this chaotic system to high order chaotic systems. After that, we introduced the method to construct the derived chaotic torus-chaotic systems. Finally, we introduced some applications such as random number generator algorithm, spread spectrum communication and image encryption schemes. The contribution of this chapter is that it systematically summarizes the design method, the dynamic behavior and typical engineering application of chaotic systems with hyperbolic sine nonlinearity, which may widen the current knowledge of chaos theory and engineering applications based on chaotic systems.
