Temple Beth Kodesh in Boynton Beach, Fla., has a Facebook page administered by Rabbi Michael Simon.

Shir Chadash is a Conservative synagogue in the New Orleans area with a Facebook page. Its rabbi, Ethan Linden, has a Twitter account.

Congregation Beth Elohim in Brooklyn, N.Y., has an active Facebook page. Rabbi Andy Bachman is its creator.

Susan Paykin is The Religious Action Center of Reform Judaism legislative assistant.

Shamash, a project of Hebrew College Online, maintains a kosher database and information on Jewish books, the Holocaust and the Tanakh, or Hebrew Bible. It includes links to all things Jewish on the Internet.

ReligiousTolerance.org has an extensive section on Jews and Judaism, including descriptions of recent controversies, including Christian Zionism, missionary efforts aimed at Jews and recent acts of anti-Semitism.

Judaism 101 is a general clearinghouse of information about Judaism run by Tracey Rich, a Jewish layperson. It contains descriptions of the Jewish calendar, the Hebrew alphabet, holidays, life-cycle events, rituals, observances and much more.

The Jewish Virtual Library is an online Jewish encyclopedia with 13,000 articles and 6,000 photographs on topics ranging from anti-Semitism to Zionism as well as statistics on numerous aspects of Jewish life.

Beliefnet, a multifaith religion website and online community, maintains a section on Judaism that includes news articles, essays, blogs, how-to’s, discussions and reviews.