A service mesh is an infrastructure layer designed to manage communication between services in microservice-based systems, often using proxies to route inter-service communications, providing features like encryption and load balancing. It separates network logic from application logic, allowing consistent management across an entire system, and is distinct from an API gateway, which handles external client requests to backend services. A service mesh typically includes a data plane, composed of sidecar proxies alongside each service to manage network traffic, and a control plane that configures these proxies. It offers benefits such as enhanced observability, security, and resilience, along with traffic management capabilities like load balancing and circuit breaking. However, its implementation can introduce challenges like added complexity and resource consumption. Service meshes improve system observability through features like distributed tracing and real-time metrics, while enhancing security with mutual TLS authentication and inter-service encryption. Kong Mesh, an enterprise-grade solution, exemplifies these advantages by supporting various environments and simplifying microservices communication management.