National Novel Writing Month is a fun, perhaps a little crazy approach to write a novel. Participants begin writing November 1 and have until November 30, by midnight, to write a 175-page (50,000-word) novel.
This experience values enthusiasm and perseverance over painstaking craft. NaNoWriMo.org wants to encourage everyone who has thought about writing a novel but has panicked about the task. As the participants have a time constraint, they have to write, write and write, what matters is the output, the quantity, not the quality. Of course, if you enroll, you are going to make many mistakes, but the point of this approach is to make writers to give themselves permission to make mistakes. It is like a shock therapy. Last year, 2007, over 100,000 participants enrolled in National Novel Writing Month, more than 15,000 of them wrote a 50,000-word novel. Have a child, plant a tree and write a book, you have heard this, haven’t you? 
