Every November, hundreds of thousands of writers around the world participate in National Novel Writing Month (NaNoWriMo), trying to churn out 50,000 words of a new novel in just 30 days. But what drives this community of amateur novel-writers, asks Sophie Robehmed.

Janelle, who has swapped her historical romance for an alternate realities story because she "can have more fun with it", is typing furiously on her tablet.

Chris, an IT professional, is thoughtfully eating a chocolate-covered fancy. Also with them are Nicole, wearing a skull hoodie and snake necklace, who works for a social enterprise, and Laura, a curly-haired twentysomething sales assistant from New Zealand.

Sitting among them, it's not long before you are asked: "Are you a NaNo?"

Three excerpts from NaNoWriMo authors "Kirsty had turned up at his Central London apartment two hours ago, completely hysterical and mumbling about her husband Jared leaving her for some hussy." Read an extract from Laura Roozendaal's Her Temporary Boss.

"Winciette closed the door on the last of the guests just as the early morning light broke through the night." Read an extract from Joy Salisbury's The Dangerous Lies of Blue Eyed Boys.

"Lisa clicked her fingers, and, suddenly, everything went quiet. Frank hadn't noticed it before, but all of the time he could normally always hear the sound of the city in the background." Read an extract from Karl Green's The Seventh Cycle.

This is a typical NaNoWriMo meet-up, at a cafe in London, where 13,000 people have been taking part in the event. Started by freelance writer Chris Baty in July 1999 with just 21 participants in San Francisco, NaNoWriMo now boasts that 300,000 people across the world have taken part this month.

The biggest tallies are in New York and London but the NaNo contingents are everywhere - there have been 4,000 in Egypt alone.

The meet-ups can be serious. Each NaNo is serious.

Image caption Quiet - genius at work

Most [novels] will be pants. Some will be OK. A few will be very good. One or two may be great Scott Pack, Publisher

"I keep doing it to try and be disciplined," says Nicole, who says completing NaNoWriMo once "felt very awesome". This is her fourth time. "I think it helps develop good habits to work on writing," she adds. "I think that's the key to writing after November." Janelle agrees. "I like writing but I never finish anything. I have ideas, I write a few thousand words and it fizzles out. I'd like to get to 61,000 this month," she says.

The NaNoWriMo meet-up sessions are organised around writing. At the cafe, a petite woman with a pierced eyebrow, Jules according to her name badge, indicates a break is over and that a 45-minute writing session is about to begin.

After the writing session, there's a 30-minute break. Halfway through the month everyone was supposed to be around the 25,000-word mark. Jules and Janelle had passed that. Laura and Nicole weren't far off but Chris was only at 2,000 words after restarting his novel completely. He seems determined to catch up.

Elmore Leonard's 10 writing tips The author described the art of writing in an article in 2001 Never open a book with weather

Avoid prologues

Never use a verb other than ''said'' to carry dialogue

Never use an adverb to modify the verb ''said''

Keep your exclamation points under control

Never use the words ''suddenly'' (see extracts) or ''all hell broke loose"

Use regional dialect, patois, sparingly

Avoid detailed descriptions of characters

Don't go into great detail describing places and things

Try to leave out the part that readers tend to skip Read the full New York Times article

Civil servant Karl, on the other hand, is dubbed a "NaNoWriMo overachiever" by fellow participants. Last year he wrote 200,000 words, which he says "nearly killed" him. This year, he's settling for 150,000. "I'm just doing 5k days and getting sufficient sleep," he tells me. "All my managers at work know I'm doing it so I get good support from them.

"I'm also in the process of watching every episode of Doctor Who ever made," Karl says. He has a Doctor Who satchel. It's perhaps no surprise that he mainly writes science fiction.

Although it has never been easier to get published, that's not really what's at the heart of NaNoWriMo. Participants are on a journey of self-discovery, attempting to tap their inner creativity. The whole event is based on the notion that getting people writing is, in and of itself, a good thing.

And the event acts as a motivational tool. Participants love writing but it's NaNoWriMo itself that inspires them to actually get the words down on paper.

For those aspirant writers who really do have dreams of being published, it's easy to take solace from JK Rowling's story - 12 rejections before achieving stellar success with the Harry Potter series.

But is there a danger that NaNoWriMo is more about quantity than quality?

"It is entirely possible to write a great novel in a month," says Scott Pack, publisher of The Friday Project, an imprint of HarperCollins. "It is unlikely, but it is possible. After all, Charles Bukowski did it with Post Office [it took one month to write, has sold millions of copies and has never been out of print in more than 40 years].

"We actually sponsored NaNoWriWe, which saw hundreds of people try to write a novel in a weekend. We published the winner and, going by the Amazon reviews, people seem to think it is very good."

But what are the chances of the amateurs? How many could make it?

Image caption Ernest Hemingway's oft used typewriter

"I do see lots of work after NaNoWriMo and some of it is pretty good," says Pack. "NaNoWriMo is a wonderful way for writers who have always wanted to get a novel finished to do just that. Most will be pants. Some will be OK. A few will be very good. One or two may be great."

Juliet Mushens, a literary agent at The Agency Group, has sold manuscripts that were conceived during the NaNoWriMo process. "But their final drafts were radically different," she says. "One author thinks maybe 6,000 words of his NaNoWriMo made it into the final work. Another whose book was sold at auction this year thinks 20,000 of hers did.

More from the Magazine Stephen Dowling explores the novel-writing journey

Read an excerpt from his unpublished novel

"What I like about it is that a strong sense of community pops up around it that gets writers really disciplined about the process and people start talking about novel writing far more than usual. I also think people are often crippled by fear of actually sitting down and trying to write. NaNoWriMo makes them do it - and gives them a huge sense of accomplishment."

A quick straw poll at a meet-up can emphasise that point. Do the participants do it hoping to get published or is the satisfaction of completing NaNoWriMo the most important factor? Satisfaction, they answer in unison.

In an era when people might go scuba diving in Bali or walking up Kilimanjaro, writing a novel is another piece in the fulfilment jigsaw. Much of what is written may not be very good, and the vast majority will never be seen by more than a handful of people, but most participants don't care about that.

Karl's word count has been growing ever since his NaNoWriMo debut six years ago. In recent years, he's been raising money for the hospice that looked after his dad shortly before he died in 2009.

"I can't run a marathon but I can do this," he says.

We published a selection of extracts from readers' novels written in a month, including Afflicted.

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