NEW YORK — Rabbi Yosef Yitzchak Kazen, a pioneer of Jewish education on the Internet and director of Chabad's cyberspace effort.

Kazen was born in Cleveland to parents who escaped Stalin's prisons and the Holocaust. His father was also a rabbi.

With the advent of computer communication technology, Kazen immediately recognized its potential for reaching an almost limitless audience, particularly people limited by geography.

In 1988, long before the Internet became popular, Kazen reached out to thousands of people on Fidonet, an online discussion network that was distributed on several thousand nodes around the world. So primitive was the technology that it would sometimes take three days for messages to travel from one part of the world to the next.

Kazen went on digitize and enter thousands of documents into what became the world's first virtual Jewish library, enabling thousands of people to learn about Judaism in an in-depth fashion.

"The title `visionary' is definitely applicable to him. He saw it when most others did not," said A. Engler Anderson, editor of Shamash—The Jewish Internet Consortium based at Boston's Hebrew College.

Michael Starr of the Jewish Theological Seminary said Kazen's site became the standard bearer for the Jewish Internet world. His "site was the one by which all the others were judged," Starr said.

Kazen's exploits in helping to set up a Passover service on a boat off Antarctica, providing information for a Jewish defense officer in Saudi Arabia, and teaching an Irish minister about Judaism earned him prominent coverage in media outlets like the New York Times, CNN, USA Today and "Good Morning America."

His outreach is immortalized in the Smithsonian Institution's National Museum of American History collections exhibit about the Internet.

In mid-1998, Kazen was diagnosed with lymphoma but refused to notify his thousands of Internet admirers. Between hospital treatments, he would log on to his laptop and respond to e-mails.

He was married and the father of six children, ages 5 to 18.