For those who might be new to the Mac, or just looking to learn their way around a little better, Apple has a really nice resource on their site: New To Mac.
See also the High Sierra Mac Basics link at the bottom of the page.
These articles cover the following topics:
- Mac setup
- Switching from Windows
- Files and folders
- Keyboard shortcuts
- Navigate with trackpad gestures
- Spotlight search
- Messages on the Mac
- iCloud sync between your devices