This document discusses Infrastructure as a Service (IaaS), one type of cloud computing service model. IaaS provides on-demand access to computing infrastructure resources like servers, storage, and networking on a pay-as-you-go basis. It allows users to host websites, applications, and build virtual data centers in a scalable and cost-effective manner. The global IaaS market is projected to see significant growth between 2019-2022 as more organizations adopt cloud computing to reduce costs while gaining scalability and flexibility.