While the "50 Shades" trilogy is the most recent bestseller to be challenged or denied by institutions like the Harford County Public Library for being "pornography," it is far from the only one.
Many top-selling books have been censored or challenged for sexually explicit material, including many works now considered classic literature or regularly used in school curriculums.
Here are just a few examples, from the top 100 books banned or challenged between 2000 and 2009, according to the American Library Association:
• The "Alice" series, by Phyllis Reynolds Taylor, was the second most banned piece of fiction in the country. Starting with the 1985 book "The Agony of Alice," the series tracks teenager Alice McKinley as she navigates relationships, sex, friendship, God and general family and life issues. In 2003, the books were the No. 1 most challenged because of their sexual content.
• "The Chocolate War," by Robert Cormier, was the third most banned book despite often being considered a classic young adult novel. The 1974 story of Jerry Renault deals with conformity and the Pandora's box that is opened after Jerry refuses to sell chocolates at his school's fundraiser. It also includes sexual situations.
• "I Know Why the Caged Bird Sings," by Maya Angelou, is sixth on the list. The 1969 work of "autobiographical fiction" follows Maya's childhood and often tragic adolescence after moving from the South to California, including an unwanted pregnancy. The book has been banned for depictions of lesbianism, premarital cohabitation, pornography and sexually explicit scenes, including rape.
• Stephen Chbosky's "The Perks of Being a Wallflower" came in at 10th place. The 1999 novel is the story of Charlie, a high-school freshman, and deals with many common high-school themes, as well as "the dilemma of passivity vs. passion," according to the book description. It has been challenged numerous times for its treatment of drugs, homosexuality, sex and suicide.
• "Forever...," by Judy Blume," was the 16th most challenged. The 1975 book describes the relationship of teenage Katherine and Michael, who fall in love and have to negotiate their sex life. Its depictions of graphic teenage sexuality have regularly drawn protests.
• Alice Walker's "The Color Purple," often considered a classic, has been the 17th most challenged book. The 1982 book has the letters of Celie, a poor, black woman talking about her life, which includes being abused and raped by her father and, later, her husband. It has also been challenged for portrayals of homosexuality and incest.
• J.D. Salinger's "Catcher in the Rye," likewise considered a classic coming-of-age novel, was the 19th most challenged book in the country during those years. The 1951 book follows 16-year-old Holden Caulfield after he leaves his prep school in Pennsylvania to spend three days in New York City. It has been regularly banned since its publication for depictions of premarital sex, prostitution and "lurid passages," among other reasons.
• The "Gossip Girl" series, by Cecily von Ziegesar, was 22nd on the list. First published in 2002, the books look at "a New York City jet-set private school populated by hard-drinking, bulimic, love-starved poor little rich kids," according to Publishers Weekly. School Library Journal notes that, in the books, "sex seems easy, no one worries about protection or consequences, the alcohol flows like water and the language is raw."
• Louise Rennison's "Angus, Thongs and Full-Frontal Snogging," is 35th on the list. The 2001 book aimed at young adults follows 14-year-old Georgia Nicolson and her humorous look at coming of age, in a diary where "nothing is sacred," according to the Amazon.com review.
The complete list of the most frequently banned books is available at http://www.ala.org.