The Atlas suite aims to make digital marketing faster, easier and more accountable so advertisers can spend more time thinking about strategy and less about execution. Atlas promises tools that help advertisers improve their bottom line.

"Atlas is a leader in campaign management and measurement for marketers and agencies," said Brian Boland, product marketing director at Facebook, in a blog post. "We believe this acquisition will benefit both marketers and users, and we'd like to explain why."

Why Facebook Bought Atlas

Boland goes on to explain that the modern marketing environment is much more complex than it was just a few short years ago. He pointed to marketers and agencies that are struggling to understand how their efforts across different channels complement and strengthen each other.

"Consequently, they are forced to adopt siloed marketing strategies for each channel, leading to poor and inconsistent end-user experiences," Boland said. "This challenge also provides an opportunity. If marketers and agencies can get a holistic view of campaign performance, they will be able to do a much better job of making sure the right messages get in front of the right people at the right time."

Facebook is betting Atlas can answer its challenges with tools that give marketers a deeper understanding of ad effectiveness and drive better digital advertising experiences for consumers.

Facebook and Atlas are no strangers. Some Facebook marketers have been using Atlas since June 2012. But Borland said Facebook plans to improve Atlas' capabilities by investing in scaling its back-end measurement systems and enhancing its current suite of advertiser tools on desktop and mobile .

"We will also work to improve the user interface and functionality with the goal of making Atlas the most effective, intuitive, and powerful ad serving, management and measurement platform in the industry," Borland said. "Ultimately, Atlas's powerful platform, combined with Nielsen and Datalogix, will help advertisers close the loop and compare their Facebook campaigns to the rest of their ad spend across the Web on desktop and mobile."

Proving Social Media ROI

Microsoft picked up Atlas as part of its $6 billion aQuantive acquisition in 2007. Atlas has been looking for a buyer for some time, and Facebook's digital advertising platform has matured enough to justify the spend.

Greg Sterling, principal analyst at Sterling Market Intelligence, told us Facebook is seeking to prove that buying ads on Facebook has a clear ROI.

"There has been debate about the value and efficacy of advertising on the site and in social media more generally," Sterling said. "One of the things that Atlas will help Facebook do is provide a better sense of ROI and attribution -- presumably showing that Facebook contributed to or was directly responsible for conversions. It's part of a broader effort that Facebook has undertaken to connect the dots between its ads and conversions, whether they be online or offline."