Abstract:  This is a talk on an introduction of various symplectic invariants and its related Hamiltonian dynamics questions. First, I will do a quick summary of current well-known invariants including spectral invariant, symplectic capacities, boundary depth, symplectic quasi-state, etc., with their related questions in Hofer geometry. Then I will demonstrate a relatively uniform method with keyword, perturbation, that how these invariants can be used to answer some of these questions. Finally, I will mention my own work on a new perturbation technique to reprove many old results and also pose some new questions. Some background on Hamiltonian Floer theory are required.