More than 70 percent of adults online now use a social networking site of some kind, according to a report by the Pew Research Center’s Internet Project, which is based on a survey of 1,801 adults in August and September 2013.

Facebook is the dominant social networking platform in terms of the number of users, Pew says, with 71 percent of online adults now using the social media site, a slight increase from the 67 percent who used Facebook as of late 2012.

But a “striking” number of users are now diversifying onto other platforms, the report says. Some 42 percent of online adults now use multiple social networking sites. Instagram users are nearly as likely as Facebook users to check in to the site on a daily basis, Pew says.

While Facebook is popular across a diverse mix of demographic groups, other sites have developed their own unique demographic user profiles, the report notes. For example, Pinterest holds particular appeal to female users (women are four times as likely as men to be Pinterest users), and LinkedIn is especially popular among college graduates and Internet users in higher income households. Twitter and Instagram have particular appeal to younger adults, urban dwellers, and non-whites. And there is substantial overlap between Twitter and Instagram user bases.

In addition to being the most commonly used social networking platform of the five measured, Facebook also has high levels of engagement among its users: 63 percent of Facebook users visit the site at least once a day, with 40 percent doing so multiple times throughout the day, Pew says.

Instagram and Twitter have a significantly smaller number of users than Facebook, but users of these sites also tend to visit them frequently. Some 57 percent of Instagram users visit the site at least once a day and 46 percent of Twitter users are daily visitors.