vCenter Server is a centralized management platform for managing virtualized environments in data centers. It allows administrators to control multiple VMware ESXi hosts and their virtual machines from a single interface, simplifying tasks like resource allocation, performance monitoring, and backup management. With vCenter Server, users can automate various processes, such as deploying new virtual machines and managing updates. It also provides features like vMotion, which enables live migration of virtual machines between hosts without downtime, enhancing flexibility and resource utilization in a virtualized infrastructure.