Istio is a service mesh platform that provides a unified way to secure communication between microservices. It operates using a control plane and data plane architecture, where the control plane manages and configures the data plane. Istio's key features include mutual TLS encryption, traffic splitting, and load balancing. It integrates with Kubernetes to streamline service discovery processes and provide advanced traffic management capabilities. Istio also provides features like Destination Rules, Virtual Services, and Role-Based Access Control (RBAC) for controlling traffic flow and security. By leveraging Istio's traffic routing, load balancing, and security features, developers can enhance the performance and security of their microservices deployments.