Apple really wants you to update to the latest macOS Sierra. And to help you along, Apple will begin automatically downloading the update to your Mac starting this week.
According to The Loop, users who have automatic downloads enabled and have enough storage for the 4.77GB download will automatically get the macOS Sierra update "over the next week."
Although it may seem a bit aggressive for Apple to automatically download the operating system for you, it's by no means as heavy handed as Microsoft was with Windows 10. Apple will only download the operating system for you, but won't install without your approval. If you're running out of room on your drive, the macOS Sierra download will be automatically deleted to allow more space for your files.
If you don't want Apple to download the update for you, head over to the Settings app on your Mac and click on the App Store. Then uncheck the option to download updates automatically.
We liked macOS Sierra for finally bringing Siri to the desktop and for its iCloud Drive improvements. There are a ton of other tweaks and enhancements that make it a clear benefit when used in conjunction with iOS devices like the iPhone 7 and Apple Watch 2.