In the fourth annual Disruptor 50 list, CNBC features private companies in 15 industries — from aerospace to financial services to cybersecurity to retail — whose innovations are revolutionizing the business landscape. These forward-thinking starts-ups have identified unexploited niches in the marketplace that have the potential to become billion-dollar businesses, and they rushed to fill them. Some have already passed the billion-dollar mark at a speed that is unprecedented. In the process, they are creating new ecosystems for their products and services. Unseating corporate giants is no easy feat. But we ranked those venture capital–backed companies doing the best job. In aggregate, these 50 companies have raised $41 billion in venture capital at an implied Disruptor 50 list market valuation of $242 billion, according to PitchBook data. Already it's hard to think of the world without them. Read more about the consumer and business trends that stand out in the 2016 list ranking and the methodology used to select this year's Disruptor companies.