Congress probing Big Tech's use of algorithms, data

The U.S. Capitol dome. Photo: Carolyn Kaster / AP

The investigation into how Russian ads and content spread on Google, Twitter and Facebook was just the beginning of Congress digging into how tech does business.

What's happening now: Lawmakers want to know everything from how algorithms filter and distribute information behind the scenes to how platforms handle consumer data to the ways extremist content spreads over social media.