Scribd, an online service for reading documents and books, has now launched its own subscription service similar to Spotify and Netflix, Wired reported.

CEO Trip Adler and his San Francisco startup unveiled the new subscription service Tuesday with the addition of major publishing house Harper Collins. Like Netflix, subscribers will not have access to the brand new titles, but will give access to a large online library.

For $8.99 per month, users can access a wide range of free content, but will also be able to purchase books not included in the subscription. Still, Adler said the company is pursuing agreements from other publishing houses as well.

"This works so well in video and music," Adler told Wired. "It's inevitable that there's something to do here in the book space too."

The idea for Scribd's subscription service is to please customers with free content and also publishers with revenue. By giving users access to a publisher's titles, they might be more inclined to buy books from other sources as well.

Also similar to Spotify and Netflix, Scribd is releasing its service on the full range of devices. Users can access the online book subscription on their computers, smartphone or tablet.

Adler attended Harvard with Scribd co-founder Jared Friedman and another entrepreneur named Mark Zuckerberg. He said, "I was in the class they made 'the Social Network' about."

Scribd was originally an online service that allowed people to easily publish documents to the web, such as legal documents and academic papers. It eventually became a tool for authors to publish articles or books and get paid for them.

The company actually has been offering its subscription service for some time, but has not publicized it. Now, subscribers can get access to Scribd's previously existing library and a plethora of Harper Collins titles, thanks to the new deal.

Scribd boasts 80 million active users and, for Jan Johnson of Red Wheel Weiser Books, that is exposure they may not otherwise be able to get.

"Scribd can convert these people over to the book subscriptions," Johnson says. "We are all for this, and we think it will just expand our audience. People will either read a book there, on the service, or buy the book in some other way if they want to keep it in their own library - either their electronic library or their real library. Some people still read books on paper."

Neither Apple nor Amazon offers a similar book subscription service, setting Scribd apart in that respect. But still, Adler and his company face tough competition in Google's Play market, Amazon' Kindle book service and Apple's iBooks.

"We expect this to change reading behavior significantly. It makes it so much easier to browse, to sample books, to read books in parallel, to search for information within books," Adler said. "That's different from what Amazon does."