Andreessen Horowitz is a private venture capital firm based in Silicon Valley, founded in 2009 by Marc Andreessen and Ben Horowitz. The firm invests in technology companies at various stages, from early startups to more established businesses, focusing on sectors like software, consumer products, and cryptocurrencies. The firm is known for its unique approach to supporting portfolio companies, offering not just capital but also resources like talent acquisition, marketing, and operational guidance. Andreessen Horowitz has backed successful companies such as Facebook, Twitter, and Airbnb, making it one of the most influential venture capital firms in the tech industry.