Q: OSX 10.11.3, in preferences, what does turning on the bluetooth option do?

Lets you connect devices such as Mouse (Magic Mouse)

It turns on Bluetooth.

Using a Bluetooth mouse, keyboard, or trackpad with your Mac - Apple Support

https://en.wikipedia.org/wiki/Bluetooth

No, the phone won't sync. If other things pair, you can delete them.

maggielou wrote:

 

OK.  I guess I really didn't ask the right question.  If I turn on the bluetooth option, does that mean that my phone will automatically sync with my computer?  If that's true, can I have only some things sync?

 

Thanks

You can sync your iPhone via WiFi (my perferred method of sync'ing my iPhone and my Mac).

With respect to iPhone, Bluetooth, Mac, if your cellular service contract includes "Tethering", then it is possible to use your iPhone as an Internet connection for your Mac.  Useful if you are away from home and do not otherwise have an internet connection for your Mac.  But most cell carriers charge and arm and a leg for the privilege of using your cell phones data connection that you already paid for, to connect your computer to that data connection.

It may also be possible to setup 1 Mac as a Bluetooth PAN server, and another Mac connect to that Mac over Bluetooth (not totally sure about this one).