National Novel Writing Month, nicknamed NaNoWriMo, starts Sunday. For the next 30 days, thousands of people across the United States will exercise their right brains and attempt to write a 50,000-word story. It's exciting, it's hard and it's worth it.

But if you're struggling to get started or considering giving up, read the words of the greats to inspire you. They'll remind you why you're doing this and give you the strength to keep going.

Whether you're taking the NaNoWriMo challenge or supporting someone else who is, here are 21 motivational quotes about writing collected from GoodReads, Thought Catalog and Writer's Digest:

“Keep a small can of WD-40 on your desk — away from any open flames — to remind yourself that if you don’t write daily, you will get rusty.” — George Singleton

“There is no greater agony than bearing an untold story inside you.” ― Maya Angelou

“There is nothing to writing. All you do is sit down at a typewriter and bleed.” ― Ernest Hemingway

“You must stay drunk on writing so reality cannot destroy you.” ― Ray Bradbury

“So what? All writers are lunatics!” ― Cornelia Funke

“A writer is someone for whom writing is more difficult than it is for other people.” ― Thomas Mann

“It ain’t whatcha write, it’s the way atcha write it.” — Jack Kerouac

“Plot is people. Human emotions and desires founded on the realities of life, working at cross purposes, getting hotter and fiercer as they strike against each other until finally there’s an explosion — that’s Plot.” — Leigh Brackett

“Start writing, no matter what. The water does not flow until the faucet is turned on.” ― Louis L'Amour

"Writers aren’t people, exactly. Or, if they’re any good, they’re a whole lot of people trying so hard to be one person." — F. Scott Fitzgerald

“Write. Rewrite. When not writing or rewriting, read. I know of no shortcuts.” — Larry L. King

“A good novel tells us the truth about its hero; but a bad novel tells us the truth about its author.” ― G.K. Chesterton

"Most writers regard the truth as their most valuable possession, and therefore are most economical in its use." – Mark Twain

“Write while the heat is in you. ... The writer who postpones the recording of his thoughts uses an iron which has cooled to burn a hole with.” — Henry David Thoreau

"The true writer has nothing to say. What counts is the way he says it." ― Alain Robbe-Grillet

“I write for the same reason I breathe ― because if I didn't, I would die.” ― Isaac Asimov

“Writing is lonely. Until that moment you write your first character and suddenly you have company.” ― Eliza Green

“The road to hell is paved with works-in-progress.” — Philip Roth

“The first sentence can’t be written until the final sentence is written.” — Joyce Carol Oates

“I love writing. I love the swirl and swing of words as they tangle with human emotions.” ― James A. Michener

"Don’t bend; don’t water it down; don’t try to make it logical; don’t edit your own soul according to the fashion. Rather, follow your most intense obsessions mercilessly." ― Franz Kafka