Introduction to Doubly Special Relativity

In these notes, based on the lectures given at 40th Winter School on Theoretical Physics, I review some aspects of Doubly Special Relativity (DSR). In particular, I discuss relation between DSR and quantum gravity, the formal structure of DSR proposal based on $\kappa$-Poincar'e algebra and non-commutative $\kappa$-Minkowski space-time, as well us some results and puzzles related to DSR phenomenology.