Blockchain technology has the potential to significantly impact developing countries through applications that increase transparency, disintermediate trust-based systems, and incentivize cooperation. However, its full potential depends on addressing challenges related to governance, identity, security, and inclusion. The document introduces blockchain concepts and discusses how decentralized networks using cryptography can build trust without centralized authorities if designed properly with the right incentive structures and consensus mechanisms. It also explores how blockchains may constitute a general purpose technology and ethical backbone for emerging technologies if developed and applied responsibly.