I am trying to make an ultrasonic distance meter using Arduino. For this I added the ultrasonic library. But on compiling it shows this error "ultrasonic.h not available". Please tell me how to add this .h file.
In you Arduino Sketch folder there is a folder called Libraries, create a folder there and put your header file in that folder and restart the Arduino IDE.
For example (PC):
You can now use it in all your projects.
If you only want to use with a particular sketch, place in in the same folder as you sketch and restart Arduino IDE.