"I am basically dividing things up. Instagram is mostly for pictures. Twitter is mostly for just saying what you are thinking. Facebook is both of them combined so you have to give a little bit of each. But yes, so Instagram, I posted more pictures on Instagram than on Facebook. Twitter is more natural."
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Teen, on using different social media sites.
Along with The Berkman Center for Internet & Society, we conducted focus groups with teenagers in a variety of locales. Here’s a list of some of the most revealing and interesting comments about how teens think about social networking sites and how they navigate issues of identity and privacy. http://pewrsr.ch/10LRth9

We asked our first stand-alone Twitter question in 2010; see how the updates have evolved.
Twitter Use 2012
May 31, 2012
15% of online adults use Twitter, with 8% using the service on a typical day. African-Americans, young adults, and mobile users stand out for their high rates of Twitter usage.
Twitter Update 2011
June 1, 2011
13% of online adults use Twitter, and half of Twitter users access the service “on the go” via mobile phone
8% of online Americans use Twitter
Dec 9, 2010
8% of online adults use Twitter. It is particularly popular with young adults, minorities, and those who live in cities.
We’ve got brand spanking new Twitter numbers out today! As of February 2012, overall Twitter adoption by online adults is at 15%, which has remained steady since May 2011, when overall Twitter adoption by Internet users was 13%. Notably, though, the % of online adults who use Twitter on a typical day has doubled since May 2011 and has quadrupled since late 2010—at that point just 2% of online adults used Twitter on a typical day. Now, 8% of online adults use Twitter on a typical day.

More key findings:
- African-Americans continue to use Twitter at very high rates—28% of online African-Americans are Twitter adopters, and 13% use the service on a typical day.
- Usage by young internet users (those 18-24 years old) increased dramatically over the last year, with nearly one in three now using Twitter.
- Our data also suggests that these trends are deeply intertwined with mobile Twitter usage on smartphones. Fully 20% of smartphone owners use Twitter overall, and 16% use the service specifically on their cell phones.
(Source: pewinternet.org)