Night Shift reduces blue light at night to aid sleep.This can be scheduled in the System Preferences app (in the Displays menu) and can be toggled on or off in the Notification Center or using Siri.Apple Pay allows vendors to embed an Apple Pay button on their websites.
This allows developers to guarantee the integrity of external files that are distributed alongside the application bundle on the same disk image.
Sierra is named after California's Sierra Nevada mountain range.
The mountain in the default desktop picture is Lone Pine Peak.
It is intended for solid-state drives and flash memory and will adopt several features found in modern file systems, such as snapshots and cloning, as well as native support for features that Apple already provides in HFS Plus through supplementary software, such as file-system encryption and TRIM support.
The file system is experimental and a release is coming in mac OS High Sierra.