Identifiers, commonly known as IDs, play a crucial role in full-stack applications by uniquely recognizing data records, with UUIDs (universally unique identifiers) being a prominent example. UUIDs offer a near-zero probability of duplication across vast datasets, making them an efficient choice for scenarios requiring unique record identification, especially in parallel data insertion. They are formatted as 32 hexadecimal characters divided by hyphens and must comply with the RFC 4122 protocol. The article outlines how to implement UUIDs in React applications using four distinct methods, each with its advantages and considerations. These methods involve employing third-party libraries like uuidv4 and react-uuid, the inbuilt crypto.randomUUID() function, and a manual approach using a raw algorithm for RFC 4122 compliance. While third-party libraries enhance developer experience, they can add performance overhead, whereas the manual method ensures a lightweight solution but requires additional setup. The importance of reliable UUID generation is underscored for maintaining the smooth operation of applications, and Clerk, an authentication provider, is mentioned for its use of KSUIDs, an advanced identifier extending UUIDs with time-based ordering.