The current state of identity systems faces a multitude of challenges that have significant implications for user privacy and security. Data duplication, fragmented credentials, and vulnerabilities within these systems create an environment ripe for identity theft and privacy breaches. To address these pressing issues, the concept of Self-Sovereign Identity (SSI) has emerged as a decentralized identification service that harnesses the power of blockchain technology. By leveraging the decentralized ledger of blockchain, SSI enables individuals to reclaim control over their digital identities. This paradigm shift from centralized authorities to user-centric control is at the core of SSI’s principles. Through SSI, individuals gain the ability to manage their personal information securely and efficiently, while enjoying the convenience of accessing service from anywhere. This article aims to provide an in-depth exploration of SSI, shedding light on its fundamental principles and architectural components necessary for implementing a functional SSI service. By understanding the core concepts of SSI, readers can grasp the potential of this innovative approach to revolutionize identity systems.