AppSumo is a leading digital marketplace offering a platform for entrepreneurs to discover, buy, and use discounted software and tools. Founded by Noah Kagan in 2010, AppSumo offers lifetime software deals, tutorials, and resources for startups and small businesses. The platform runs on a deal-based model with limited time offers on various tools like SEO, social media marketing, graphic design, and more. AppSumo is not only a marketplace but also an educational platform, offering free learning resources and eBooks for budding entrepreneurs.