Public libraries in the United States are truly local institutions. Many years ago I was told by a corporate official that if you want to know what a town is really like, go to its public library.

Public libraries in all of Maine towns and cities are unique, except in one fact: they are all funded at the local level. Sometimes people think since they are called “free” public libraries, they don’t cost anything to run. That’s not true.

Most public libraries in Maine are funded through a combination of municipal funding, private donations and, if they are fortunate, endowment income. Even the small reading rooms located in our tiniest hamlets, run by volunteer staff, cost money to run.

The Bangor Public Library reflects the fact that Bangor is a city of readers. The generosity of its users was seen yet again when the plea went out this summer for money to add air conditioning to the building to stop mold found growing in one of its corners.

More than 1,980 people donated an average of $115 to match a state New Century Grant that will allow the library to add air conditioning before next summer.

Library board and staff are grateful for everyone’s generosity.

The library also received a grand piano through a grant from the Arthur Vining Davis Foundation and a gift from a local pianist and teacher and her physician husband.

Patricia Stowell, Dean Stein, Sophie and Josie Davis performed the dedication concert. We at the library hope this is a start of a regular series of community concerts.

The Bangor Public Library plays many roles in the community. It preserves and makes available the city’s history and genealogy. It is a place to go for popular books, magazines, newspapers, audio books and videos.

It is a preschooler’s door to reading, a place for students to find more information, and for life-long learning to bloom. The library is a computer center and an Internet connection as well as a community center.

It is a place to get timely, accurate information and to connect to other libraries across the world so anyone can conduct in-depth studies, investigate any subject and become part of the creative economy.

Books for the Bangor Public Library come from income generated by the library’s endowment funds. This money has been donated over the years by many Bangor residents and allows the library to continue to buy materials of interest to its many patrons.

In most Maine towns and cities, around 53 percent of the residents have a local library card. In Bangor, 72 percent of the residents have a current, valid library card and have used the library during the past year. There are 41,189 registered borrowers at the Bangor Public Library.

Donations make the library a very special place in our city, but to keep the doors open, the lights on and the staff working, the library depends on the city’s support, too.

At 6 p.m. Tuesday, Oct. 26, Ardeana Hamlin, author of “Pink Chimneys” and “A Dream of Paris,” will be the latest in the library’s Meet the Author series.

Barbara McDade is director of Bangor Public Library.