Yahoo Marks 20 Years With Yodels, Reminiscences

On its home page, Yahoo displayed an animated birthday cake as part of its logo, and the company launched a series of events marking its trademark "Yahoo yodel."

On the Nasdaq stock exchange in New York, the opening bell was transformed into a yodel and in San Francisco an attempt was being made to set a record for the largest simultaneous yodel.

Yahoo was incorporated on March 2, 1995 by two Stanford University electrical engineering students, Jerry Yang and David Filo, who originally called it "Jerry and David's Guide to the World Wide Web."

They renamed it Yahoo, jokingly saying it was an acronym for "Yet Another Hierarchical Officious Oracle."

"It wasn't designed to be a business, it was simply something we found useful. When we realized other people found it useful, we were motivated to work on it even more," Filo said in a blog post.

"Twenty years later, the core of Yahoo is still the same. We are driven by the same purpose to be your guide around the web. You may not know how much you motivate us every day by using our products and sharing your ideas, but you do. Thank you."

Over the years, Yahoo has fallen behind in its original mission as a search engine and been through several attempts at reorganization and restructuring.

Filo said that "technology is about constant reinvention," adding that "every day brings something new and in many ways, it feels like we're just getting started."

Chief executive Marissa Mayer, who moved from Google in 2012, has been focusing on mobile services and media, including music and original television programming.

The company on Monday launched its TV Digital Magazine, the latest in a series of new products aimed at making Yahoo a destination.

Yahoo news anchor Katie Couric posted a video of one of the celebrations on Twitter, one of many posts using the hashtag #YodelOn.