Topological insulators, with their gapless edge states around a gapped insulating bulk, have attracted a great deal of theoretical and experimental efforts recently. While their topological nature is usually attributed to fermions filling a topological band structure, , I will show in this talk that similar phases exist in interacting boson / spin systems as well. This talk is going to give a general introduction to such Symmetry Protected Topological (SPT) Phases, which include nontrivial bosonic topological insulators and superconductors in one, two and three spatial dimensions. In particular, I am going to focus on the exotic edge physics such SPT phases can have, spin / boson models where they are realized, and the classification of SPT phases with group cohomology.