On the page, it will serve up a hot steaming cup of of 418 response code, which is a server status code. This status code is named, “I’m a teapot”, and was an April Fools Joke all the way back from 1998. Due to the fact this was simply a joke from Google, there was no intention of of being implemented or supported, but Google has found a way to implement it anyway.
Barry Schwartz of Search Engine Land spotted the easter egg when Google’s John Mueller hinted to it on Google+. When you click on the teapot, you’ll watch the teapot top and pour out some tea into the cup below it, and the same thing will happen if you tilt your mobile device to the side.
Here is a video that Barry made to demonstrate: