A well-stocked Little Free Library stands along State Highway 46 in Amery.

The concept is simple: Take a book, share a book.

But for many communities, urban as well as rural, Little Free Libraries are much more than that; they’ve become “beacons of neighborliness and friendliness, and that’s always a good thing,” according to Margret Aldrich of the Little Free Library program, a Hudson nonprofit established in 2012.

“People are always looking for a way to connect with each other, and this is a really easy way to do that, especially if you love books and love to read and want to give something back to your community,” said Aldrich, author of “The Little Free Library Book.”

Now the biggest book-sharing movement in the world, Little Free Library was launched in 2009 by Hudson native and UW-River Falls graduate Todd Bol, who passed away last year at the age of 62. While renovating his garage, he admired the old wooden door and didn’t want to throw it away. He decided to build a small monument in honor of his mother, who was a teacher, turning the door into a two-foot-tall schoolhouse replica. He filled it with some of his mother’s books and put it in his front yard in hopes of starting a book exchange with neighbors.

Before long, orders came in for more little libraries, which Bol made with help from an Amish craftsman. Do-it-yourselfers sought specifications to make their own. Within a couple years, and without issuing any news release to publicize the effort, he had inspired the building of more than 2,500 little libraries. Now, more than 75,000 Little Free Libraries have been planted in all 50 states and 88 countries worldwide.

“It was one simple idea that struck a chord around the world,” Aldrich said.

The book-filled boxes aren’t limited to city street corners, suburban malls and subway stations; they’ve also cropped up in cornfields and wooded areas. One for reindeer herders and their families can be found in Siberia. In a remote area of Canada, a couple carved one out of a dead ash tree; it’s closed in the winter months as people can’t access it due to snow.

The libraries come in all shapes, including bird feeders, barns, log cabins and mini-replicas of the house in front of which they stand. Aldrich said many small public libraries use them to better reach rural readers who can’t regularly get to their nearest facility.

The 75,000th library was donated to a school in Oklahoma that is very diverse, with many immigrant and refugee families, Aldrich said. Students there speak more than 30 languages. They use their Little Free Library as a “connecting point,” she said.

Operating under the honor system, the content of the boxes is constantly changing, as people take a book and leave one behind for others. Each box contains at least 20 books. Tens of millions of books have been shared through the libraries, and as a side benefit, thousands of neighbors have met each other for the first time.

Anyone can install a tiny library and become a “steward” of it, using their discretion as far as the box’s contents. People can construct their own, and about 65 percent of stewards do; purchase one through the program; or, through the donor-driven Impact Library Program, apply to receive one at no cost, along with a supply of books.

“We definitely want whoever wants to have a Little Free Library to be able to have one,” she said. “Finances shouldn’t be prohibitive.”

Aldrich said they receive more applications for libraries than they can fulfill, but all of those who apply are “kept in the loop” for possible future funding.

She said they ask that those who build their own get it registered with the program so they’re documented and “we can tell your story.”

While the open, outside libraries often are vulnerable to vandalism, Aldrich said, very few of them — only about 5 percent — fall victim, and if something happens, community members are quick to rally around it and complete the necessary repairs and restocking.

Little Free Library is celebrating its 10th anniversary this year by awarding the Todd H. Bols Awards for Outstanding Steward Achievement, or “Toddy,” awards; distributing commemorative Little Free Libraries; incorporating technology to improve the experience for volunteer stewards and patrons; and with new ways for people to get involved in the global book-sharing movement.

In the next year, Aldrich said, they hope to have 100,000 Little Free Libraries established worldwide. While California is home to the most Little Free Libraries in the U.S., Wisconsin and Minnesota have the most per capita, she said.

In an increasingly digital age, Aldrich sees the impact of the program every day: “People are talking more; we’re seeing kids with books in their hands walking home.”