One switch in System Settings turns Location Services off for the whole Mac, and every app and system service under it has its own. Sharing your location with people is a different switch again, inside Find My. Apple says that even with Location Services off, third-party applications and websites may still use other ways to determine your location.
Do they get told?Whether anyone is told that you turned Location Services off on a Mac is not documented on Apple's page. What Apple does document is the effect: your precise location is no longer sent to Apple, and apps and websites stop getting your position from Location Services.
Who can still see you
Off
Apps and websites on this Mac
They stop getting your position from Location Services, and Apple says your precise location is no longer sent to Apple.
Still on
Find My Mac and your other devices
Find My Mac and the location sharing in Find My are separate switches and stay exactly as you left them.
Still visible
Websites and the network
Apple says third-party applications and websites may still use other ways to determine your location. Your IP address alone places you roughly.
Apple's page says your Mac works out where it is from information from local Wi-Fi networks.
Do they get told?Apple does not document a notification to the people you were sharing with. It documents what changes on their side: when you stop sharing, your contact can no longer see you in Find My, and all location notifications they created about you are turned off.
Who can still see you
Off
Everyone you were sharing with
Every share ends at once and the location alerts your contacts set up about you are turned off with it.
Still on
Find My Mac, and every app
Locating your own Mac and each app's Location Services switch are separate and stay on.
Still visible
Websites and the network
Your IP address and the Wi-Fi networks around you still place you roughly, whatever Find My is set to.
Apple's page says that if you only have a Mac, you can't share your location: the share comes from an iPhone, iPad, iPod touch or Apple Watch on the same Apple Account.
Do they get told?A notification to that person is not documented on Apple's Mac page. What is documented is that the contact can no longer see you in Find My, and that all location notifications they created about you are turned off.
Who can still see you
Off
That one person
You disappear from their Find My, and any location alerts they set up about you stop with the share.
Still on
Everyone else you share with
Only one share changed. Share My Location and every other person on the People list stay as they were.
Still visible
Websites and the network
Your IP address and the Wi-Fi networks around you still place you roughly, whatever Find My is set to.
The same page prints Hide Location in the My Location section as the way to pause a share rather than end it.