Arduino UNO USB

Hello guys:
I have just uploaded the new program to my new Arduino Uno, it worked great. But now, I don't know how to turn this Arduino Uno off.
I am currently powering up the Arduino using the USB, where can I safely eject my Arduino from my computer?

You should not need to eject the UNO just pull the USB connection out, preferably when the serial monitor is closed.

It isn't a mass-storage device so it doesn't need ejecting.

Thank you for helping me!!