Cloud infrastructure and virtualization form the backbone of modern computing. These technologies enable on-demand access to shared computing resources, revolutionizing how businesses operate and scale. From physical data centers to virtual machines, they provide the foundation for flexible, efficient, and cost-effective IT solutions. This unit explores the key components of cloud infrastructure, including service models like IaaS, PaaS, and SaaS. It also covers virtualization technologies, deployment models, and management tools, providing a comprehensive overview of the cloud computing landscape and its real-world applications across various industries.