Invited Talk: The Extragalactic Gamma-ray sky
Our knowledge of the extragalactic gamma-ray sky is evolving very rapidly as new data becomes available. I will present recent results on the gamma-ray emission from extragalactic sources based on the latest Fermi-LAT catalogs (3FGL-3LAC and 2FHL), on new large samples of multi-frequency selected gamma-ray and VHE emitting blazars (1WHSP and 2WHSP), and from extensive Monte-Carlo simulations of gamma-ray surveys of blazars. Specific predictions for the present generation of Cherenkov telescopes and for the upcoming CTA will be presented. This will include the number of detectable sources, their redshift distribution, and the contribution of blazars to the extragalactic gamma-ray and VHE background.