have to "draw" to kill the ghosts. On February 11, 12, 13 and 14, 2017, for Valentine's Day, Google added a game featuring the endangered pangolin, an African and Asian mammal, that goes through four levels (one released each day), while collecting objects, and avoiding obstacles. On 28 February 2017, Google celebrated Edhi with a Google Doodle hailing his "super-efficient" ambulance service. On May 9, 2017, a Google Doodle was featured honoring the 181st birthday of Ferdinand Monoyer. He was a French ophthalmologist, who introduced the dioptre in 1872. Dioptre is the unit of measurement of the focusing power of the lens. It is like the distance between a person's eyes and the text to be read. Monoyer devised an eye chart where every row represents a different diopter, from smallest to largest. A close look at Doodle may reveal to the reader a tribute to Ferdinand Monoyer: his name, hidden in the chart. On June 22, 2017, to celebrate what would have been the 117th birthday of Oskar Fischinger, a musician, Google released an interactive fullscreen Doodle that let users create their own musical songs by tapping on the screen. The user could then choose to share it to social media. The game was accessible by tapping on 2 play buttons. On August 11, 2017, the 44th anniversary of DJ Kool Herc's pioneering use of the hip hop break, the Google Doodle allowed users use a double turntable to act as a hip-hop DJ. On September 4, 2017, to celebrate what would have been the 83rd birthday of Russian baritone singer Eduard Khil, Google added a video doodle that featured an animated Eduard Khil singing "I am very glad, as I'm finally returning back home", known globally as the "Trololo" song. On December 4, 2017, Google celebrated 50 years of kids' coding languages with an Interactive Doodle. On January 29, 2018, Google celebrated Taiwanese singer Teresa Teng on what would have been her 65th birthday. On May 3, 2018, Google celebrated the work of Georges Méliès by making a doodle that encompassed his famous work such as A Trip to the Moon and The Impossible Voyage. The doodle is also the first google doodle that was shown in 360-degrees format, with the viewer being able to rotate the video to give them different points of view. On June 10, 2018, Google celebrated the history of garden gnomes by releasing