Nearly 20 percent of U.S. adults don't use the Internet. That means that roughly 60 million people, many of them elderly, poor and minorities, have no access to technology the rest of us increasingly consider mission-critical to modern life.

The New York Times’ has an interesting story today on that phenomenon, which lays out some of the programs policymakers have tried to use to get people online. But that got us wondering about who these 60 million people are and whether they’re offline by choice or circumstance -- a question that is not, in fact, as obvious as you might think.

Internet adoption has more or less flatlined in recent years, according to data from the Pew Internet and American Life Project. As of the center’s last survey in May, somewhere between 81 and 85 percent of U.S. adults were online. The number with home Internet access is significantly lower -- roughly 72 percent, according to the Census Bureau.

The people on the offline side of the digital divide are, demographically speaking, probably who you’d expect. Wealthier people have more Internet than poor people; penetration is lowest among adults older than 65.

But there are also some disturbing racial differences that concern academics and policymakers. While Internet use more than doubled in Hispanic and black households since 2000, they still lag significantly behind white and Asian households -- who, at 82.7 percent, have the highest Internet use of any surveyed groups.

There’s also a stubborn rural versus urban gap in Internet connectivity and frequency of access. Per the Commerce Department, 74 percent of urban households use the Internet, versus 62 percent of rural households. That gap gets even worse when it comes to broadband adoption -- 72 (urban) versus 58 (rural) percent. Non-users tend to live in the southeast.

So why don’t people go online? The Department of Commerce tried to answer that very question in a June report on America’s “Emerging Online Experience” -- which, as the department notes, hasn’t quite emerged in some corners of the country. Intriguingly, the agency found that half of offline households simply don’t want Internet -- they either feel they don’t need it, they can use it elsewhere, or it infringes on their privacy. For the remaining non-users, the big factor is cost.

Statistically, however, most people are wrong when they say they don’t need the Internet. Per the Commerce Department, Internet use has a measurable impact on employment, income, consumer welfare and civic engagement. So closing the digital divide would not only benefit individuals on the wrong side of it, but also the economic and civic society as a whole.