How to include libraries, just search the name and find the first one?

I've read this: https://www.arduino.cc/en/guide/libraries

I'm trying to get this example to work: github.com/mikaelpatel/Arduino-OWI/blob/master/examples/Slave/DS18B20/DS18B20.ino

When compiling it, it says I do not have the libraries:

fatal error: GPIO.h: No such file or directory

 #include "GPIO.h"

                  ^

compilation terminated.

exit status 1

I downloaded the .zip file. I extracted it, and put the whole master folder in Arduino → libraries. Now do I need to just search GPIO.h and throw it in the libraries folder? This is the first one that comes up: github.com/esp8266/Arduino/blob/master/tools/sdk/include/gpio.h

I've used the Library Manager before. But this way is different. It just seems odd having to download the large ESP8266 Arduino master folder just for one library. And that's another thing I don't understand--I'm not even using an ESP8266 for this project.

Where am I going wrong?

(deleted)

adamaero:
I downloaded the .zip file.

The page where you downloaded that zip file has a heading "Dependencies" near the bottom. One of them is Arduino-GPIO. It's the library you need to install.

Thank you GypsumFantastic. :-[