Google has had many logos since its renaming from BackRub. The current official Google logo was designed by Ruth Kedar, and is a wordmark based on the Catull typeface. The company also includes various modifications and/or humorous features, such as cartoon modifications of their logo for use on holidays, birthdays of famous people, and major events, such as the Olympics. These special logos, some designed by Dennis Hwang, have become known as Google Doodles.
In 1998, Sergey Brin created a computerized version of the Google letters using the free graphics program GIMP. The typeface was changed and an exclamation mark was added, mimicking the Yahoo! logo. "There were a lot of different color iterations", says Ruth Kedar, the graphic designer who developed the now-famous logo. "We ended up with the primary colors, but instead of having the pattern go in order, we put a secondary color on the L, which brought back the idea that Google doesn't follow the rules."
In 2010, the Google logo received its first major and permanent overhaul since May 1999. The new logo was first previewed on November 8, 2009, and was officially launched on May 6, 2010. It utilises an identical typeface to the previous logo, but the "o" is distinctly more orange-colored in place of the previously more yellowish "o", as well as a much more subtle shadow rendered in a different shading style. On September 19, 2013, Google introduced a new "flat" (two-dimensional) logo with a slightly altered colour palette.
The current Google logo was launched on September 19, 2013. The major difference in comparison with the previous logo was the flattening of shadows on the lettering to be consistent with the company's current user interface. It was launched to everyone on October 2, 2013.