Most tweets are worthless.

That’s what Twitter users told researchers at Carnegie Mellon in 2011. They said that only one-third of the tweets they receive are worthwhile.

Perhaps the 140-character messages would be worthwhile if they contained links. According to several studies, roughly 25 percent of all tweets contain a link. Not much when you think about. (Tweets with links, said self-described social scientist Dan Zarrella, are more likely to earn a retweet.)

What kind of links are people in that 25 percent sharing?

Difbot Page Classifier, an app that determines the page of any Web link, analyzed 750,000 links posted to Twitter. Turns out, images are the most commonly shared links, followed by articles, videos, and products.

Not too surprising when you consider 2012 is the year of the image, in which sites such as Pinterest and Instagram are enjoying booming popularity.

The surprising part of the study is the most popular source for the articles—it’s not CNN, BBC, Yahoo, or any English-speaking site for that matter. It’s Detik.com, the largest online media site in … Indonesia.

To see more results from the study, check out the infographic: