To most Google, Yahoo, Facebook, Twitter, Tumblr, Flickr, Foursquare, Skype, Instagram, YouTube, Vine and/or Pinterest users, this may sound crazy, but there are actually people who do not use the Internet.



According to a study released Wednesday by the Pew Research Center’s Internet Project, some 15 percent of American adults aged 18 and older do not use the Internet. Among those non-Internet users, about a third (34 percent) say they are "not interested, do not want to use it, or have no need for it." Another third (32 percent) say it is "difficult or frustrating" to go online, that they are physically unable or they are worried about security issues "such as spam, spyware, and hackers." About 1 in five people who do not use the Internet say it's too expensive, and 7 percent lack physical access.



“A lot of people are surprised to discover that not everyone is online,” Pew's Kathryn Zickuhr said in a release accompanying the findings. “Most offline adults either don’t see the internet as relevant to them, or feel that it would not be worth the effort."



According to the survey of 2,252 adults conducted earlier this year, 44 percent of Americans aged 65 and older do not use the Internet. And the 65-plus set make up nearly half of non-Internet users overall, Pew found.



But "offline adults" are not totally disconnected from the Internet. Forty-four percent say they have asked a friend or family member to look something up on the Internet or complete an online task for them. (Twenty-three percent of non-Internet users live in a household that has Internet access.) And 14 percent say they used to use the Internet, "but have since stopped for some reason."



Most non-Internet users say they have no plans to become users anytime soon. The study found that the vast majority (92 percent) of offline adults have no interest in going online in the future, while only 8 percent would like to start using the Internet or email.



The disinterest may have something to do with ability. A majority of non-Internet users (63 percent) say they would need assistance getting online.



The survey's margin of error was 2.3 percentage points, Pew said.



























