The document summarizes Chris Anderson's Long Tail theory, which proposes that the availability of niche products and markets on online platforms allows their collective demand to match or even exceed that of mainstream hits. It explains that while physical stores focus on hits due to shelf space limitations, online retailers like Amazon can offer virtually unlimited products. This enables the "long tail" of less popular niche goods to be accessed by interested consumers and together rival the demand for hits. The theory has proven true as niche markets satisfying narrow interests have grown significantly online.