OS X Yosemite 10.10.4 released

Today Apple released OS X Yosemite 10.10.4, introducing many bug and security fixes. Of note for people who have been experiencing excessive processor usage and network issues since upgrading to OS X Yosemite, Apple reverted from the new Discoveryd process to the previous mDNSresponder that existed in OS X Mavericks and prior which many people found to be more stable.

To update your Mac, click the Apple Menu, choose App Store, click the Updates tab, and when the page fully loads click the Update button.