The document discusses the four main deployment models of cloud computing: private cloud, public cloud, community cloud, and hybrid cloud. For each model, it provides details on architecture, benefits, and limitations. The public cloud is available for general use and resources are shared, while the private cloud is dedicated for a single user. The community cloud allows resource sharing among specific organizations. A hybrid cloud combines public and private cloud models to achieve cost-effectiveness, security, and scalability benefits while addressing their individual limitations.