SAN FRANCISCO (AP) — The co-founders of Google are stepping down as executives of its parent company, Alphabet, ending a remarkable two decades during which Larry Page and Sergey Brin shaped a startup born in a Silicon Valley garage into one of the largest, most powerful — and, increasingly, most feared — companies in the world.

Sundar Pichai, who has been leading Google as CEO for more than four years, will take on additional duties as Alphabet’s CEO, the position held by Page. The company isn’t filling Brin’s position as president.

Page and Brin met as Stanford University graduate students in 1995 and started the company soon after.

What started as a way to catalog the growing internet has now become one of the most powerful companies in the world. Google dominates online search and digital advertising and makes the world’s most widely used operating system for smartphones, Android. It’s hard to make it through a whole day without using one of Google’s services — ranging from online tools to email, cloud computing systems, phones and smart speaker hardware.

Yet Google has been facing pressure from privacy advocates over its collection and use of personal information to target advertising. It also faces allegations that it abuses its dominance in search and online advertising to push out rivals.

Google is the subject of antitrust inquiries from Congress, the Department of Justice and a contingency of states in the U.S. and from European authorities. The company has also faced harsh criticism about the material on its sites — and was slapped with a $170 million fine because its video streaming site YouTube improperly collected personal data on children without their parents’ consent.

In the short term, longtime tech analyst Tim Bajarin of Creative Strategies doesn’t expect much to change at the company. And if anything does, he said, it will be due to government regulation — not the executive shuffle.

Pichai assured employees in an internal email that his new job wouldn’t mean he was taking a step back from Google.

“I want to be clear that this transition won’t affect the Alphabet structure or the work we do day to day,” he wrote. “I will continue to be very focused on Google and the deep work we’re doing to push the boundaries of computing and build a more helpful Google for everyone.”