Zappos is an online shoe and clothing retailer founded in 1999 that has experienced rapid growth through a focus on exceptional customer service. Some key points: - Zappos has over 8 million customers and 75% of purchases are from repeat customers who spend more on average than new customers. - They prioritize fast, free shipping and easy returns to provide the best shopping experience for customers. - Word-of-mouth from satisfied customers has been the main driver of growth, with little spent on traditional advertising.