For the Art Genome Project, Matthew Israel, 34, who holds a Ph.D. in art and archaeology from the Institute of Fine Arts at New York University, leads a team of a dozen art historians who decide what those codes are and how they should be applied. Some labels (Art.sy calls them “genes” and recognizes about 800 of them, with more added daily) denote fairly objective qualities, like the historical period and region the work comes from and whether it is figurative or abstract, or belongs in an established category like Cubism, Flemish portraiture or photography.

Other labels are highly subjective, even quirky; for contemporary art, for example, Art.sy’s curators might attach terms like “globalization” and “culture critique” to give ideological context. “Contemporary traces of memory” is an elastic theme assigned to pieces by the Chinese Conceptual artist Cai Guo-Qiang and the photographer and filmmaker Matt Saunders.

A Picasso might be tagged with “Cubism,” “abstract painting,” “Spain,” “France” and “love,” all terms that are visible and searchable on the site. Jackson Pollock’s works typically get “abstract art,” “New York School,” “splattered/dripped,” “repetition” and “process-oriented.” Predictably, some of those criteria show up on paintings by Pollock’s contemporaries Robert Motherwell and Willem de Kooning, but also on artists from different eras and styles, like Tara Donovan, whose contemporary abstract sculptures using stacked and layered plastic foam and paper plates have also been marked with “repetition.”

As the categories are applied, each is assigned a value between 1 and 100: an Andy Warhol might rate high on the Pop Art scale, while a post-Warholian could rank differently, depending on influences. Software can help filter images for basic visual qualities like color, but the soul of the judgment is human.