Local libraries have joined the digital revolution in books.

Now you can check out a library book on an e-reader rather than having to lug home the physical book. Check out a book from home and have it on your e-reader in minutes any time of the day or night.

And if you don’t have an e-reader, you can check one out at your local library.

The Brookfield and Riverside public libraries have e-readers available to check out now and the North Riverside Public Library will have some in just a few weeks.

The e-readers have proved popular in Brookfield and Riverside right from the start.

In Brookfield, all of its eight e-readers, four Barnes & Noble color Nooks and four Sony Readers, were checked out within 48 hours of being made available on May 2.

“They’re all checked out,” said Debbie Griggs the head of Reference and Electronic Services at the Brookfield Public Library. “They were all checked out by Wednesday.”

It’s the same story in Riverside, which stared offering e-readers for checkout a few weeks ago.

“Since we’ve started there is at least six holds on them already,” said Janice Fisher, the director of the Riverside Public Library, which has one Nook and one Sony e-reader available for check out for the last month or so.

Library card holders in North Riverside won’t have to wait long to be able to check out an e-reader.

“I think it’s going to reach a segment of our population that we’re not reaching now,” said Robert Lifka, the director of the North Riverside Public Library.

When someone checks out an e-reader, they then go to a website and, with their library card number, can download one of thousands of books to the device. When they return the e-reader to the library, the book is removed from the device.

Checking out an e-reader is a great opportunity to see if you like reading a book on a screen before taking the plunge and buy an e-reader. They are particularity good for those with vision problems, because text can be enlarged.

Currently you can’t borrow digital library books to read on an Amazon Kindle, the most popular e-reader, but that will change by the end of year. Local libraries are excited by the development and are getting ready.

“We will be purchasing Kindles in the next month or so,” Fisher said.

Griggs said that she expects that the Brookfield Public Library will purchase Kindles by the end of the year. It cost the Brookfield Public Library about $2,000 to purchase its eight e-readers.

Libraries pay an annual fee to what is called My Media Mall or another such service so their patrons can download e-books. The fee is based on population. The annual My Media Mall fee for the Brookfield Public Library is $2,541. The Riverside Public Library pays about half that, $1,210 per year.

Riverside-Brookfield High School purchased six Kindles for its library about two months ago and purchased 46 popular and recreational reading titles that have been downloaded to RBHS’ Kindles, said Doreen Fritz, head librarian at the school.

The Kindles have been a hit with high school students.

“The response has been very positive,” Fritz said. “Students are loving the Kindles.”

Fritz said that it is unlikely that RBHS would soon join the service that allows thousands of books to be borrowed and then downloaded to the Kindles, because it is too expensive and money is tight at RBHS.

“I’m not sure we’ll go in that direction,” Fritz said. “Eventually we want to move in that direction.”

Lovers of old-fashioned printed books need not worry that the e-readers will replace bound books from libraries any time soon.

“Will it replace print books? No, but it’s a nice alternative,” Fisher said.