In addition to celebrating many well-known events and holidays, Google Doodles celebrate artists and scientists on their birthdays, including Mary Somerville, Andy Warhol, Albert Einstein, Leonardo da Vinci, Rabindranath Tagore, Louis Braille, Ella Fitzgerald, Percival Lowell, Edvard Munch, Nikola Tesla, Béla Bartók, René Magritte, Norman Hetherington, John Lennon, Michael Jackson, Vladimir Dakhno, Robert Moog, Akira Kurosawa, Satyajit Ray, H. G. Wells, Freddie Mercury, Samuel Morse, Hans Christian Ørsted, Mahatma Gandhi, Dennis Gabor, Édith Piaf, Constantin Brâncuși, Antonio Vivaldi, Abdel Halim Hafez, Jules Verne, Leonhard Euler, Lucille Ball, Hedy Lamarr, and James Welch, among over 9,000 others. The featuring of Lowell's logo design coincided with the launch of another Google product, Google Maps. Google Doodles are also used to depict major events at Google, such as the company's own anniversary. The celebration of historic events is another common topic of Google Doodles including a Lego brick design in celebration of the interlocking Lego block's 50th anniversary. Some Google Doodles are limited to Google's country-specific home pages while others appear globally.