John Maloof didn’t know what street photography was when he purchased several boxes of Vivian Maier’s photographs at the RPN Sales Inc. auction house in 2007. Maloof, a 29-year-old former Chicago real estate agent, now lives by the term.

Eighty of Maier’s photos are currently on display at the Chicago Cultural Center, 78 E. Washington St., in an exhibit called “Finding Vivian Maier: Chicago Street Photography,” which runs through April 3. Maloof, a local historian, quit his job  and became a full-time archivist of Maier’s work. His efforts put Maier on the map, but he won’t take full credit.

“The story and the photos have gone viral,” Maloof said, referring to the Internet’s ability to spread news rapidly.

Lanny Silverman, curator of exhibitions at the Chicago Cultural Center,  agrees.

“I’ve got people all over the world saying, ‘I saw your WTTW interview on YouTube!’ It’s a phenomenon,” Silverman said.

Maier, a reclusive nanny who had a passion for photography, never showed her photographs to anyone. Between 1951 and 1995, Maier walked the streets of Chicago on her days off, photographing what she saw. According to Maloof, she had no children, love life or known family and kept mostly to herself. He also said there is no evidence she was trained in photography.

She spent time in New York City in the ’50s and also traveled to Egypt, Italy and Manila, among other locations, documenting her time there. Maier lived with her employers, usually wealthy North Shore families, and brought her boxes of film and prints with her to each new home.

When the elderly Maier could no longer afford the storage space where she kept her 100,000-plus prints and negatives, they were sold at auction. Maloof stumbled across the photographs by chance, looking for pictures to put in his book about Chicago’s Portage Park neighborhood. After Maloof read Maier’s obituary in the Chicago Tribune in 2009, he uncovered the mystery of the woman behind the camera.

Though Maloof decided he couldn’t use them for his book, the pictures continued to fascinate him.

“I realized this work is special,” he said. “I didn’t know if it would be acclaimed by experts, but I knew it was special to me.”

Maloof began archiving the photos and scanning the negatives in his free time. With the help of RPN Sales Inc., he was able to find most of the other people who purchased Maier’s work and bought it from them. In the meantime, he started a blog with some of the pictures and linked it to a Flickr discussion group titled “Hardcore Street Photography.” He explained his story and received an outpouring of advice and help, which led him to contact the cultural center.

“When I saw them, I got very excited,” Silverman said. “[Maier] had an incredible eye and a wide range of styles. She incorporated Helen Levitt, Harry Callahan and Diane Arbus, among others.”

While Silverman said the photographs are great, the media attention helped create a buzz surrounding the exhibit.

“I’ve had far bigger and more ambitious shows that I had trouble to even drag out,” Silverman said. “[Sometimes] I couldn’t even get a review for the life of me. Now it’s the other way around. My wife called her friends in England and told them to check out the photography. They had already seen it in the UK Journal.”

The media buzz has driven attendance at the cultural center since the exhibit opened on Jan. 8.

“It’s been hugely popular,” said Christine Carrino, communications manager at the Chicago Cultural Center. “Critically, the response has been overwhelming. The opening night was packed wall-to-wall.”

Maloof has dedicated himself to sharing Maier’s work and her story with the world.

A documentary film titled “Finding Vivian Maier” is set to come out in 2012. Maloof and Anthony Rydzon, a friend who assisted Maloof in uncovering Maier’s mystery, are producing the film. The two have created a Web video asking for donations to help with the process and have tripled their goal so far.

“Vivian’s legacy is finally taking shape and it’s beautiful,” Maloof said. “It was almost doomed for the dark abyss of closets from the people [who] bought them. These could have very easily been thrown out.  And it’s amazing they just skimmed by a thread, and now they are renowned as some of the best street photography people have seen in decades.”