Abstract：Laser cooling and trapping of atoms embarks an exploration into a new world where quantum mechanics dominates all laws of motion. New tools to precisely manipulate the atoms are developed, which remarkably advance quantum simulation and quantum metrology. I will outline in this lecture the basics of quantum control with cold atoms, as well as examples of quantum simulation of nuclear, condensed matter and gravitational systems. Finally I will outline our new experiment to gain full control of a many-body Hamiltonian toward scalable quantum information processing.