Lean Startup is a set of processes used by entrepreneurs to develop products and markets, combining Agile Software Development, Customer Development and existing software platforms (usually FOSS). Lean Startup leverages the latest technology to create product prototypes in weeks, and use customer feedback to evolve them in near real-time. It is not uncommon to see Lean Startups release new code to production multiple times a day, a process known as Continuous Deployment.
Lean Startup is sometimes described as Lean Thinking applied to the entrepreneurial process. A central tenet of Lean Thinking is to reduce waste. Lean Startup processes use Agile Development to reduce waste by increasing the frequency of contact with real customers, therefore testing and avoiding incorrect market assumptions as early as possible.
This approach attempts to improve on historical entrepreneurial tactics by reducing the work required to assess assumptions about the market, and to decrease the time it takes a business to find market traction. This is referred to as Minimum Viable Product. Lean Startup draws heavily upon the Customer Development process, as described in the book The Four Steps to Epiphany.