Night Shift, the feature first introduced in iOS devices with iOS 9.3, has expanded to the Mac with the release of 10.12.4. Night Shift is compatible with 2012 and newer Macs, so it won't work on older machines.
For those unfamiliar with Night Shift, it's designed to cut down on the amount of blue light you're exposed to during the evening by shifting the display of a Mac to a more yellow...