Eight in ten online teens (80%) now use social network sites such as Facebook or MySpace, up from just over half of online teens (55%) the first time we measured social network site usage among teenagers in late 2006. Social network site adoption among teens is significantly higher than it is among adults as a whole; 64% of all online adults use these sites. However, adults under the age of 30 use these sites at roughly the same rate as teens; 87% of online 18-29 year olds are social network site users.

Twitter adoption among teens pales in comparison to their use of social network sites as a whole. Yet, the number of teen Twitter users has doubled over the last two years; 16% of online teens now use Twitter, up from 8% the first time we asked this question in late 2009. Teens and adults now use Twitter at similar rates, as 12% of online adults are Twitter users.

Almost all teen Twitter users take part in other online social network sites as well—just one respondent in our survey reported using Twitter but not using any other social network sites.¹⁴ Throughout the remainder of this chapter and in the report that follows, the 80% of online teens who use social network sites and/or Twitter will be referred to as teen social media users. They comprise 76% of all those ages 12-17.