NEW YORK (AP) — There were many kinds of best-sellers in 2011 and they sold in different ways.

Some were meant for success, such as Walter Isaacson's "Steve Jobs" or Tina Fey's "Bossypants" or Stephen King's "11/22/63." Some were surprises, such as Todd Burpo's "Heaven Is for Real" and Adam Mansbach's "Go the (Bleep) to Sleep."

Some books thrived on the Internet alone. Amanda Hocking's vampire romance novels were self-published, ebook million sellers. So were John Locke's crime novels and Darcie Chan's small-town story of a secluded widow, "The Mill River Recluse."

Ebooks have grown to around 20 percent of the market and the percentage should keep rising in 2012 as millions of ever-cheaper devices are purchased. The e-pull proved strong enough to persuade a famous holdout, J.K. Rowling, and a nearly as famous resister, Ray Bradbury, to go digital. The e-library of older works expanded greatly in 2011, with additions including Alice Walker's "The Color Purple," Joseph Heller's "Catch-22" and Jim Collins' business favorite "Good to Great." Expect digital versions of Tennessee Williams' plays in the near future.

But the e-revolution remains in its early stages and books can still sell big through paper alone. Mansbach's "Go the (Bleep) to Sleep," the summer's forbidden pleasure, was a sensation before an e-edition was available. Jeff Kinney's latest "Diary of a Wimpy Kid" sold 1 million copies in its first week, all on paper.

Meanwhile, some key works remain untouched by digital times, including a few likely to appear on reading lists for the foreseeable future:

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