When using includes such as #include <Wire.h> , where in my Windows folders is the file Wire.h ?
What did you do to try to find it?
I'd try file explorer, search for "Wire.h".
If it's win10 probably here:
C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries\Wire\src
.. if installed for all users.
If installed for one user: C:\Users\NAME\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.6\libraries\Wire\src\wire.h
This is the one for UNO R3.
There may be several copies of this file when other processors/boards are installed.
Searched for the file name on all my drives. If it's included in a sketch I assume it must be somewhere on my PC.
Arduino on my PC is in C:\Program Files\Arduino IDE with no hardware folder.
If installed for one user: C:\Users\NAME\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.6\libraries\Wire\src\wire.h
Got it. Thank you.
You could also find it by inspecting the compiler reporting, if you go to Preferences and enable more verbose reporting. The default settings hide a whole lot of useful information.