vSphere is a cloud computing virtualization platform developed by VMware. It allows users to create, manage, and run virtual machines on physical servers, enabling efficient resource utilization and flexibility in IT environments. With vSphere, organizations can consolidate their hardware, reduce costs, and improve scalability. It includes features like vCenter Server for centralized management and ESXi hypervisor for running virtual machines, making it a popular choice for businesses looking to optimize their IT infrastructure.