Mini-review on Collider Signatures for Extra Dimensions

In this talk, I briefly review collider signatures for two models of extra dimensions. The first one was proposed by Arkani-Hamed {\it et al.} that gravity is free to propagate in extra dimensions of very large size ($\alt 1$ mm). Collider signatures for this model can be divided into two types: (i) emission of real gravitons into extra dimensions, and (ii) exchanges of virtual gravitons. The second model was proposed by Pomarol {\it et al.} and Dienes {\it et al.} that the SM gauge bosons are allowed to propagate in extra dimensions. Collider signatures for the second model are due to the existence of the Kaluza-Klein (KK) states of $\gamma$, $W$, $Z$, and $g$ bosons.