Container-based virtualization in fog computing is a growing research area that focuses on leveraging lightweight container technologies, such as Docker and Kubernetes, to efficiently manage, deploy, and orchestrate applications across distributed fog environments. Unlike traditional virtual machines, containers provide faster startup times, lower overhead, and greater portability, making them highly suitable for resource-constrained fog devices. Research papers in this field explore container-based resource allocation, service placement, task scheduling, and workload migration strategies that optimize latency, scalability, and Quality of Service (QoS). Studies also highlight multi-tenant container orchestration frameworks that enable isolation, dynamic scaling, and resilience in heterogeneous fog–edge–cloud ecosystems. Recent works investigate the integration of container-based virtualization with microservices architectures, software-defined networking (SDN), and network function virtualization (NFV) to enhance flexibility and adaptability. Security and privacy-aware container management solutions are also emphasized to mitigate vulnerabilities inherent in multi-tenant environments. Applications include real-time IoT data processing, smart healthcare, vehicular networks, industrial automation, and AR/VR, where fast, scalable, and reliable deployment is crucial. Overall, research in container-based virtualization for fog computing provides efficient, portable, and resilient solutions for managing distributed services in next-generation computing systems.