Forrest J Ackerman, who influenced a generation of young horror-movie fans with Famous Monsters of Filmland magazine and spent a lifetime amassing what has been called the world's largest personal collection of science-fiction and fantasy memorabilia, has died. He was 92.

Ackerman, a writer, editor and literary agent who has been credited with coining the term "sci-fi" in the 1950s, died Thursday of heart failure at his home in Los Angeles, said John Sasser, a friend who is making a documentary on Ackerman.

As editor of Famous Monsters of Filmland, Ackerman wrote most of the articles in the photo-laden magazine launched in 1958 as a forum for past and present horror films.

"It was the first movie-monster magazine," Tony Timpone, editor of horror-movie magazine Fangoria, told The Times in 2002.

Timpone, who began reading Famous Monsters as a young boy in the early '70s, remembered it as "a black-and-white magazine with cheap paper but great painted [color] covers. It really turned people on to the magic of horror movies."

Primarily targeted to late pre-adolescents and young teenagers, Famous Monsters of Filmland featured synopses of horror films; interviews with actors such as Boris Karloff, Bela Lugosi and Vincent Price; and articles about makeup and special effects.

The magazine reflected Ackerman's penchant for puns, with features such as "The Printed Weird" and "Fang Mail." Ackerman referred to himself as Dr. Acula.

"He put a lot of his personality into the magazine," said Timpone, who became friends with Ackerman. "It was a pretty juvenile approach to genre journalism, but as kids that's all we had."

Among those who grew up reading Famous Monsters of Filmland was author Stephen King. Other childhood readers included movie directors Joe Dante, John Landis and Steven Spielberg, who once autographed a poster of "Close Encounters of the Third Kind" for Ackerman, saying, "A generation of fantasy lovers thank you for raising us so well."

Ackerman was a celebrity in his own right, once signing 10,000 autographs during a three-day monster-movie convention in New York City.

This, after all, was the man who created and wrote the comic book characters Vampirella and Jeanie of Questar and was the ultimate fan's fan: a man who actually had known Lugosi and Karloff and whose priceless collection of science-fiction, horror and fantasy artifacts ran to some 300,000 items.

For years, Ackerman housed his enormous cache of books, movie stills, posters, paintings, movie props, masks and assorted memorabilia in his 18-room home in Los Feliz.

He dubbed the house the Ackermansion. The jam-packed repository included everything from a Dracula cape worn by Lugosi to Mr. Spock's pointy ears and from Lon Chaney Sr.'s makeup kit to the paper-plate flying saucer used by director Ed Wood in "Plan 9 From Outer Space."

For Ackerman, a native Angeleno born Nov. 24, 1916, it all began at age 9.

That's when he stopped at a drugstore on the corner of Santa Monica Boulevard and Western Avenue in Hollywood and bought his first copy of the science-fiction magazine Amazing Stories.

Ackerman was helplessly hooked.

By his late teens, he had mastered Esperanto, the invented international language. In 1929, he founded the Boys Scientifiction Club. In 1932, he joined a group of other young fans in launching the Time Traveler, which is considered the first fan magazine devoted exclusively to science fiction and for which Ackerman was "contributing editor."

Ackerman also joined with other local fans in starting a chapter of the Science Fiction Society -- meetings were held in Clifton's Cafeteria in downtown L.A. -- and as editor of the group's fan publication Imagination!, he published in 1938 a young Ray Bradbury's first short story.

During World War II, Ackerman edited a military newspaper published at Ft. MacArthur in San Pedro. After the war, he worked as a literary agent. His agency represented scores of science-fiction writers, including L. Ron Hubbard, Isaac Asimov, A.E. van Vogt, H.L. Gold, Ray Cummings and Hugo Gernsback.