To understand the future, it helps to appreciate the past. That’s one of the guiding principles of the UCLA Festival of Preservation, which showcases more than two dozen films and other projects that have been lovingly saved from the extinction by the efforts of the UCLA Film and Television Archive and others.

The UCLA Festival of Preservation, held at the Billy Wilder Theater at the Hammer Museum, runs through March 30 and is marking its 25th anniversary.

The fest, held every two years, always aims for an eclectic screenings sked, according to Jan-Christopher Horak, director of the archive. Projects range from rarely seen short subjects and newsreels to silent features (“Mantrap,” “Midnight Madness”) to Robert Altman’s dark 1969 drama “That Cold Day in the Park.” There are also a number of TV excavations, including a night dedicated to Julie Harris’ smallscreen work and a Sam Peckinpah-directed seg of ABC’s “Stage 67.”

“This well-rounded festival is pretty much a trip through our whole archive,” Horak said. “There is a heavy emphasis on classic Hollywood material because that’s how it started and that’s what’s around us.”

But preserving 50- to 100-year-old films is not a simple copy and paste process.

“First, we find the best material available of original negatives, which isn’t always easy,” Horak said. “We’ll make new materials based off that but sometimes scenes are missing or we need to re-record sound tracks. That means some films can take six months and others can take three to four years.”

With this lengthy process and only a month to display restored work, the films shown are mostly chosen by an outside faction: the funders.

“It really depends on funding sources and that decides what is preserved initially,” Horak said. “They want to support the archive and want to know what’s going on with it.”

The UCLA Film & Television Archive is the second-largest moving image archive in the United States. “Short Films of the 1910s” is among the oldest restoration project on this year’s fest line-up, featuring eight clips that look back on a decade of rapid transformation in American film.

For a full festival sked to go to Cinema.ucla.edu

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