The search engine Google is celebrating its 12th birthday anniversary. It is celebrating its 12th birth day with a cake's picture, on which the "L" letter in Google is represented by a burning candle.This special occasion is celebrated the Google way with a very special Google doodle as in the picture. Google has been commemorating special days with its much-talked-about doodles. The first of such doodle had appeared in August 1998 when its founders Sergey Brin and Larry Page designed one for the Burning Man Festival.According to media reports, the birthday doodle is a work of Wayne Thiebaud, a famous artist who is associated with the Pop art movement. It was reproduced by permission of VAGA, Visual Artists and Galleries Association.In April 2007, Google bought DoubleClick, a company specializing in Internet advertising for 3,100 million dollars. Earlier this month, Google became the world's most valuable brand, reaching the sum of 66,000 million dollars, beating flagship companies like Microsoft, General Electric and Coca-Cola. In September 2010, Google implemented "Google Instant Search", a feature that allows to search as the user is typing the search term.