Born in Teaneck, New Jersey, Cassyd worked for the Army Signal Corps as a film editor under then-Col. Frank Capra during World War II.
After the war, Cassyd moved to Hollywood, where he worked as an editor for Box Office magazine, as well as a grip at Paramount Pictures.
While at KTLA, Cassyd felt that TV needed an organization in which people could share their ideas about the fledgling medium and talk about the future of the industry.
Cassyd founded the Academy of Television Arts & Sciences in 1946, which has grown into one of the most influential organizations in the entertainment industry.
In addition to sponsoring the annual Emmy Awards, which recognize outstanding entertainment and news achievement in television, the academy has a variety of outreach and archival programs.