A Service Node is a component in a network that provides specific services to other nodes or clients. It can handle tasks such as data processing, storage, or communication, acting as a mediator between users and resources. Service nodes are essential in distributed systems, where they help manage workloads and improve efficiency. In cloud computing, service nodes can be part of a larger architecture, such as a microservices framework. They allow for scalability and flexibility, enabling applications to run smoothly by distributing tasks across multiple nodes. This setup enhances performance and reliability in systems like Amazon Web Services or Microsoft Azure.