BBW: What's the difference between a challenge and a banning?

Banned Book Week (BBW) 2014: What is the difference between a challenge and a banning?

According to the American Library Association:

"A challenge is an attempt to remove or restrict materials, based upon the objections of a person or group. A banning is the removal of those materials. Challenges do not simply involve a person expressing a point of view; rather, they are an attempt to remove material from the curriculum or library, thereby restricting the access of others. Due to the commitment of librarians, teachers, parents, students and other concerned citizens, most challenges are unsuccessful and most materials are retained in the school curriculum or library collection." ~American Library Association's About Banned & Challenged Books

Looking to learn more on Banned Books Week?  Visit the American Library Association's Banned Book Week Website for information on Banned Book Week and the history of the event.