macOS High Sierra offers better security, performance and stability.
macOS High Sierra introduces new core technologies that improve the most important functions of your Mac. From rearchitecting how it stores your data to improving the efficiency of video streaming to unleashing the full power of your graphics processor, it’s all central to today’s Mac experience.
Upgrade your macOS to High Sierra from macOS Sierra is really simple.
First, click on the apple logo, and “About this Mac”
A window will be opened, here you need to click “Software Update…”
Now, the App store will be opened. If you see the High Sierra banner – click “free upgrade” or click “update” – right to the “Software update” item.
If some dialogs pops out and saying you need to close things – that’s fine, accept and High Sierra will start installing.
Your Mac might reboot several times.
When you see the login screen, you are done!
Don’t forget to make a backup first!