Infrastructure as a Service (IaaS) is one of the three fundamental models of cloud computing, alongside Platform as a Service (PaaS) and Software as a Service (SaaS). IaaS enables businesses to create and manage virtual machines and other computing resources through a web interface or an API. This significantly reduces the need for physical infrastructure investment and management, allowing organizations to scale their IT resources up or down based on demand. Users can provision new servers quickly, manage workloads efficiently, and optimize resource utilization, often leading to cost savings.