SAN FRANCISCO (AP) — A new study says half of all American adults are now on social networks, and use among Baby Boomers is growing.

A report from the Pew Internet & American Life Project says that of the adults who use the Internet, nearly two-thirds use social networks such as Facebook or Twitter. That's up slightly from a year ago.

Among Baby Boomers, those Americans born between 1946 and 1964, 32 percent say they use a social networking site on a typical day. That's up from 20 percent a year ago.

Seniors are also testing the waters of social networking.

Pew says its survey, which was released Friday, was conducted April 26 to May 22 among 2,277 adults.