Title: Diary of a Wimpy Kid (film series)
Content:  Diary of a Wimpy Kid is a series of family comedy films based on the book series of the same name by Jeff Kinney. The series currently consists of four theatrical films and an animated film.
Title: Diary of a Wimpy Kid (book)
Content:  Diary of a Wimpy Kid is the first book in an ongoing franchise. A total of sixteen Wimpy Kid books have been released, the sequels to the first book are: Rodrick Rules (2008) which was listed on the New York Times Best Sellers list for 117 weeks, The Last Straw (2009) which was on the New York Times Best Sellers list for 65 weeks, peaking at number one, Dog Days (2009) which was ranked at number one on the New York Times Best Sellers List for all 25 weeks of inclusion, making it the #1 best selling book of 2009, The Ugly Truth (2010), Cabin Fever (2011), The Third Wheel (2012), Hard Luck (2013), The Long Haul (2014), Old School (2015), Double Down (2016), The Getaway (2017), The Meltdown, (2018) , Wrecking Ball (2019),, The Deep End (2020), and Big Shot (2021).
Title: Diary of a Wimpy Kid (book)
Content:  Diary of a Wimpy Kid is a children's novel written and illustrated by Jeff Kinney. It is the first book in the Diary of a Wimpy Kid series. The book is about a boy named Greg Heffley and his attempts to become popular in his first year of middle school. Diary of a Wimpy Kid first appeared on FunBrain in 2004, where it was read 20 million times. The abridged hardcover adaptation was released on April 1, 2007. The book was named a New York Times bestseller, among other awards and praise. The book was adapted into a live action feature film, which released on March 19, 2010, and an animated film adaptation was released on Disney+ on December 3, 2021.
Title: Diary of a Wimpy Kid
Content: Diary of a Wimpy Kid (April 1, 2007) ; Diary of a Wimpy Kid: Rodrick Rules (February 1, 2008) ; Diary of a Wimpy Kid: The Last Straw (January 13, 2009) ; Diary of a Wimpy Kid: Dog Days (October 12, 2009) ; Diary of a Wimpy Kid: The Ugly Truth (November 9, 2010) ; Diary of a Wimpy Kid: Cabin Fever (November 15, 2011) ; Diary of a Wimpy Kid: The Third Wheel (November 13, 2012) ; Diary of a Wimpy Kid: Hard Luck (November 5, 2013) ; Diary of a Wimpy Kid: The Long Haul (November 4, 2014) ; Diary of a Wimpy Kid: Old School (November 3, 2015) ; Diary of a Wimpy Kid: Double Down 
Title: Diary of a Wimpy Kid
Content:  Diary of a Wimpy Kid is an American fiction book series and media franchise created by author and cartoonist Jeff Kinney. The series follows Greg Heffley, who illustrates his daily life in a diary. Kinney spent eight years working on the book before showing it to a publisher. In May 2004, FunBrain and Kinney released an online version of Diary of a Wimpy Kid. The website made daily entries until June 2005. The online version received almost 20 million views as of 2009. Nonetheless, many online readers requested a printed version. In February 2006, during the New York Comic Con, Kinney signed a multi-book deal with publisher Abrams Books to turn Diary of a Wimpy Kid into a print series. The first installment was 
Title: Diary of a Wimpy Kid
Content:  in April 2007 to immediate success. In April 2009, Time magazine named Kinney to the Time 100 most influential people. Sixteen books in the series have been released as of 2021; an activity book has also been released. A spin-off series, centering on the character Rowley Jefferson, has three installments as of 2021. The first, second, fourth and ninth installments have been adapted into films by 20th Century Fox; two books have been released chronicling the production of the films. Since the release of the online version in May 2004, most of the books have garnered positive reviews and commercial success. As of 2021, more than 250 million copies have been sold globally, making it the sixth best-selling book series of all time.
Title: Diary of a Wimpy Kid: The Ugly Truth
Content:  Diary of a Wimpy Kid: The Ugly Truth is a 2010 bestselling children's fiction book by American author and cartoonist Jeff Kinney and is the fifth book in the Diary of a Wimpy Kid series. The Ugly Truth sold 548,000 copies in its initial week of publication, edging out Decision Points, which sold 437,000 copies. Kinney initially struggled with the decision of whether Greg would be a non-aging "cartoon character" or a literary character that would age and go through puberty, deciding to make puberty one of the book's themes. Kinney also debated over whether to end the series with five books, eventually deciding to continue the series.
Title: Diary of a Wimpy Kid
Content:  A spin-off series has been published, written from Rowley's perspective. The first installment, Diary of an Awesome Friendly Kid: Rowley Jefferson's Journal, was released on April 9, 2019, and is a series of anecdotes about Greg and Rowley's friendship. The second, Rowley Jefferson's Awesome Friendly Adventure, is in the style of a fantasy adventure and was released on August 4, 2020. The book's original release date was April 7, 2020, but was delayed due to the COVID-19 pandemic. The third, Rowley Jefferson's Awesome Friendly Spooky Stories, was released on March 16, 2021.
Title: Diary of a Wimpy Kid (2010 film)
Content:  A tie-in book, written by Kinney, called The Wimpy Kid Movie Diary, was published on March 16, 2010, by Amulet Books (an imprint of Abrams Books). It includes film stills, storyboards, preliminary concept drawings and also behind-the-scenes information to humorously chronicle the making of Diary of a Wimpy Kid, Diary of a Wimpy Kid: Rodrick Rules, and Diary of a Wimpy Kid: Dog Days. It also includes some new illustrations.
Title: Diary of a Wimpy Kid: Old School
Content:  Diary of a Wimpy Kid: Old School is a children's novel written by American author Jeff Kinney first published in 2015. It is the tenth book of Diary of a Wimpy Kid series, preceded by Diary of a Wimpy Kid: The Long Haul and followed by Diary of a Wimpy Kid: Double Down. The book was released on November 3, 2015 worldwide, though an extract from the book was released online on October 27, 2015.

Question: how many books are in the diary of a whimpy kid series?
Answer: 12.