The document discusses the "deal a day" business model, where a single product is offered at a discounted price for 24 hours. If a minimum number of customers sign up, the deal is available to all. This reduces risk for retailers. Variations include longer time periods and progressively decreasing prices. Revenue comes from the number and size of deals, number of geographic areas, and categories. Customers benefit from deep discounts and access to new products. The model works best for businesses with high fixed or customer acquisition costs that rely on repeat customers. Merchants typically retain 50% of revenue after credit card fees and see 80% redemption rates.