Retina display with 2560-by-1600 resolution on the 13-inch model Fourth-generation dual-core Intel Core i5 (13-inch model) Intel Iris Graphics in the 13-inch model and Intel Iris Pro Graphics Up to 9 hours (13-inch model) Faster flash storage2 802.11ac Wi-Fi Two Thunderbolt 2 ports for connecting high-performance devices and transferring data at lightning speed Two USB 3 ports (compatible with USB 2 devices) and HDMI FaceTime HD camera OS X, the world’s most advanced desktop operating system 1 Battery life varies by use and configuration.