CONTAGIOUS: WHY THINGS CATCH ON by Jonah Berger (Simon & Schuster), 244 pages, $29.99 cloth. Rating: NNNN
What turns an idea, a dance or a haircut into a meme? How do videos go viral? What makes one business succeed while another flounders? Jonah Berger, a professor of marketing at the University of Pennsylvania, uses relevant examples and layman's language to lay out a blueprint for those hoping to make their product or idea contagious.
His fast-paced book focuses on six key factors he terms STEPPS, an acronym for social currency, triggers, emotion, public, practical value and stories.
A New York City bar called Please Don't Tell was accessed by an unmarked door in the wall of a phone booth. People were proud to find the bar through the secret passageway and shared this tidbit with friends, giving it free viral love - no advertising budget required. That's how social currency works.
When it comes to triggers, Berger cites iconic chocolate bar Kit Kat's self-reinvention through association with drinking coffee, causing consumers to think Kit Kat whenever they bought java. By the end of a year, sales had increased 8 per cent.
Emotion plays a key role in what we like to share with friends. Berger and his colleagues studied thousands of New York Times articles on the paper's most-shared list and discovered that those on scientific subjects were shared more than entertainment stories because they aroused readers' awe.
Things succeed when they go from private to public. Look at the Movember campaign to raise awareness of prostate cancer. Few health campaigns have had such a visible symbol - a guy sporting a moustache - to remind us about a rarely discussed issue.
Practical value proves important when instructional clips and content make their way across social media.
And finally, telling a good story can increase a product's visibility. That's why Subway, instead of pumping out stats and slogans, shows Jared explaining how he lost weight eating its sandwiches.
Social science books seldom reveal such a compelling step-by-process to lift the curtain on those viral memes that pop up in conversation or on our Twitter feeds.