A microservice is a software architecture pattern where applications are composed of small, independent services that communicate through APIs. Each service handles a specific function, allowing for greater flexibility and scalability. In the context of cloud computing, microservices can be deployed and managed independently, enabling organizations to scale applications more efficiently. This architecture supports continuous integration and continuous delivery by allowing teams to update individual components without affecting the entire system. Furthermore, the use of microservices aligns well with cloud environments, enhancing resource optimization and reducing operational costs.