sierra os
is it possible to upgrade from os x Yosemite to os sierra
Question marked as
If your Mac meets the criteria then yes, read this, How to upgrade to macOS Sierra - Apple Support and if it can upgrade to Sierra it can upgrade to High Sierra, read this, How to upgrade to macOS High Sierra - Apple Support
Before you upgrade make a full back up of your Mac. Open Disk Utility and run First Aid on your disk to check for errors, if errors are found you will need to boot to your Recovery Drive and run Disk Utility> First Aid until the errors clear.
Check with developers of any third party apps you use that they have updates available for the macOS you choose to install. Also check with the manufacturers of any printers/ scanners or other devices you use with your Mac that there are updated drivers and software for your new OS.
