Jew

The Jewish people are an ethno-religious group on Earth, with a religion that worship God. Many members of the faith can read or speak Hebrew.

In 2365, a hologram representing a comic mentioned a Jewish person in one of his jokes. 

Two Orthodox Jews passed a newspaper stand on the streets of New York where Benny Russell had talked to a newspaper salesman earlier. 

In 2374 a holographic Nazi SS officer in a World War II holoprogram run by the Hirogen on the USS Voyager remarked that Jews would fall defeated before peoples of German ancestry. 

Background
The Vulcan salute, first featured in the TOS Season 2 episode, is modeled on a benediction hand sign done with both hands by Jewish Kohanim (descendants of the ancient priests) when blessing the congregation of a Jewish synagogue. Leonard Nimoy, who improvised the salute, remembered it from his childhood and suggested it to the show's director.

Numerous mytho-religious Jewish people have been mentioned in Star Trek, including Moses, David, and Solomon. At the same time, several prominent 20th century Jews have also been referenced including Albert Einstein, Isaac Asimov, and The Marx Brothers.

Theodore Bikel and Georgia Brown, who played Sergey and Helena Rozhenko respectively, are noted in the entry on the episode in the Star Trek: The Next Generation Companion as being well-known in the Yiddish theater. The Companion suggests that this background, coupled with their characters' last name, Rozhenko, implies that Worf's parents are Jewish.

Apocrypha
Jewish characters have appeared in numerous Star Trek novels. These include:
 * Darya Bat-Levi, in Well of Souls by Ilsa J. Bick, identifies as Jewish and discusses the religion at length.
 * David Rabin, in Vulcan's Forge by Susan Shwartz (who is also Jewish) identifies as of "Earth Israeli descent". Though some Israelis are not Jewish, "David Rabin" is a Hebrew name, suggesting he is.
 * Aaron Stemple, in Ishmael by Barbara Hambly, has a Hebrew name, and does not eat pork (which is forbidden in Judaism).
 * Harb Tanzer, in Diane Duane's The Wounded Sky and Spock's World speaks fluent Yiddish (an East-European Jewish language, lit. Jewish).
 * Myron Shulman, in Recovery by J.M. Dillard, has funeral conducted in accordance with Jewish tradition, including a minyan (ten men) reciting Kaddish (an Aramaic prayer used in Judaism).
 * Jael Rabinowich, in The Final Reflection by John M. Ford, has a Yiddish name and uses the Hebrew phrase "Shalom aleichem" (lit. "Peace be upon you", colloquially, "Hi, how are you")
 * David Steinberg, in Yesterday's Son by A.C. Crispin
 * Lena Goldblum, in Star Trek Log 5 by Alan Dean Foster, the Jewish roommate of M'Ress who plays with a dreidel (a spinning top associated with the festival of Chanukah).
 * Saul Weinstein, in Brad Ferguson's Crisis on Centaurus, uses Yiddish expressions.
 * Dora Grayson in Strangers from the Sky by Margaret Wander Bonnano. A Professor Grayson (Amanda Grayson's great-great grandfather) states that his wife, Dora, was Jewish.
 * David Gold, captain of the USS da Vinci and his wife, Rabbi Rachel Filman, in the Star Trek: Starfleet Corps of Engineers series identify as Jewish, as do their descendants.
 * Several SCE stories have been devoted to Gold's Judaism, including "An Easy Fast" in Tales from the Captain's Table (which takes place on the fast of Yom Kippur, the Jewish Day of Atonement) and Creative Couplings which discusses the marriage of Gold's granddaughter to the son of a Klingon ambassador.