Try Moon and Tides Lab free in your browser, with nothing to install and no account. See the Earth, Moon and Sun from above and from a beach on the ground at the same moment. Drag the Moon round and watch its shape change in the sky, turn on Earth's shadow to see why it is not the cause, and find out why there is not an eclipse every month. Then watch two high tides a day come from the same Moon, and read a real coast's tide for a month.