A Google Doodle is a special, temporary alteration of the logo on Google's homepages intended to commemorate holidays, events, achievements, and historical figures. The first Google Doodle honored the 1998 edition of the long-running annual Burning Man event in Black Rock City, Nevada, and was designed by co-founders Larry Page and Sergey Brin to notify users of their absence in case the servers crashed. Early marketing employee Susan Wojcicki then spearheaded subsequent Doodles, including an alien landing on Google and additional custom logos for major holidays. Google Doodles were designed by an outside contractor, cartoonist Ian David Marsden until 2000, when Page and Brin asked public relations officer Dennis Hwang to design a logo for Bastille Day. Since then, a team of employees called Doodlers have organized and published the Doodles.

Initially, Doodles were neither animated nor hyperlinked—they were simply images with tooltips describing the subject or expressing a holiday greeting. Doodles increased in both frequency and complexity by the beginning of the 2010s. On October 31, 2000, the first animated Doodle celebrated Halloween. On May 21, 2010, the first interactive Doodle appeared later celebrating Pac-Man, and hyperlinks also began to be added to Doodles, usually linking to a search results page for the subject of the Doodle. By 2014, Google had published over 2,000 regional and international Doodles throughout its homepages, often featuring guest artists, musicians, and personalities. By 2024, the Doodlers team had created over 5,000 Doodles for Google's homepages around the world.

In addition to celebrating many well-known events and holidays, Google Doodles celebrate artists and scientists on their birthdays. The featuring of Lowell's logo design coincided with the launch of another Google product, Google Maps. 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.

Since the first Thanksgiving Doodle in 1998, many Doodles for holidays, events and other celebrations have recurred annually. These include:

Doodlers is Google's name for the illustrators, engineers and artists who design the Doodles. They have included artists like Ekua Holmes, Sophia Foster-Dimino, Lynnette Haozous, and Eric Carle.

In May 2010, on the 30th anniversary of the 1980 arcade game Pac-Man, Google unveiled worldwide their first interactive logo, a playable Pac-Man Google Doodle, created in association with Namco. Anyone who visited Google could play Pac-Man on the logo, which featured the letters of the word Google on the Pac-Man maze. The logo also mimicked the sounds the original arcade game made. The I'm Feeling Lucky button was replaced with an Insert Coin button. Pressing this once enabled the user to play the Pac-Man logo. Pressing it once more added a second player, Ms. Pac-Man, enabling two players to play at once, controlled using the W, A, S, D keys, instead of the arrows as used by Player 1. Pressing it for a third time performed an I'm Feeling Lucky search. It was then removed on May 23, 2010, initially replacing Pac-Man with the normal logo. Later on that day, Google released a permanent site to play Google Pac-Man (accessed by clicking on top icon), due to the popular user demand for the playable logo. Pac-Man Doodle drew an estimated 1 billion players worldwide.

Since that time, Google has continued to post occasional interactive and video doodles:

Google holds competitions for school students to create their own Google doodles, referred to as Doodle 4 Google. Winning doodles go onto the Doodle4Google website, where the public can vote for the winner, who wins a trip to the Googleplex and the hosting of the winning doodle for 24 hours on the Google website.