Here’s a Timeline of Yahoo’s 22-Year History as a Digital Pioneer

Highs and lows leading up to Verizon deal

Verizon's $4.8 billion acquisition of Yahoo today shows just how much has changed in the Sunnyvale, Calif., company's more than 20-year history.

Yahoo's gone from being one of the world's biggest companies in online search to an internet company that's struggled in recent years to move beyond display advertising. Now, Verizon wants to build a digital advertising and media company that rivals Google—one of Yahoo's longest-standing competitors—as well as Facebook and others. According to Zenith Media, Alphabet, Google's holding company, controls 12 percent of all global media spend, meaning Verizon and AOL have their work cut out for them.

"The acquisition of Yahoo will put Verizon in a highly competitive position as a top global mobile media company, and help accelerate our revenue stream in digital advertising," said Lowell McAdam, Verizon CEO and chairman, in a statement.

The timeline below shows some of the 22-year-old company's highs and lows, acquisitions, and other noteworthy events. If nothing else, Yahoo's history serves as a cautionary tale of the potential pitfalls of building a digital powerhouse that's constantly forced to reinvent itself, particularly when it comes to relying on advertising for money.

1994: David Filo and Jerry Yang launch Yahoo—an acronym for Yet Another Hierarchically Organized Oracle—as a catalog for managing websites.

1996: Yahoo, valued at $848 million, goes public.

2000: Yahoo hits its highest valuation at $125 billion thanks to the dot-com boom.

2002: Then CEO Terry Semel puts in a $3 billion bid to acquire Google. The rising search player turned down the offer.

2005: Yahoo invests $1 billion in Chinese e-commerce player Alibaba, a 40 percent stake.

2008: Yahoo turns down a $44.6 billion acquisition deal from Microsoft aimed at building a competitor to Google.

2011: Yahoo pushes into web video, launching Yahoo Screen—a hub of original content including NBC's Community. Yahoo Screen is shut down in January 2016.

2012: The company poaches Google exec Marissa Mayer as CEO to help turn around the struggling internet company as revenues from display advertising continue to slip.

2013: Mayer acquires hot social network Tumblr for $1.1 billion—her first big acquisition—with the aim of reaching a millennial audience.

2014: Mayer launches 11 digital magazines across food, tech, sports and lifestyle. In February 2016, seven of the verticals—health, parenting, food, makers, travel, automotive and real estate—are shut down.

2014: Yahoo acquires mobile app analytics company Flurry and programmatic video player BrightRoll to build up its ad-tech stack. Pre-Verizon, rumors swirl that AOL wants to buy Yahoo to build a programmatic, data-driven platform.

2015: The company signs a deal with Google to place some ads and search features on Yahoo search listings. It also partners with the NFL on the league's first online-only livestream, broadcasting a game between the Buffalo Bills and Jacksonville Jaguars at London's Wembley Stadium.

2016: Tumblr partners with video apps YouNow, Kanvas and YouTube to power livestreaming on the site. Unlike similar efforts from Facebook, Twitter and Google, Tumblr plugs into existing video apps, so it doesn't not need to build a platform to power the technology.