The document discusses different cloud computing models including Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). It notes that PaaS builds on IaaS and allows developers to deploy applications without managing the underlying infrastructure. Examples of PaaS providers mentioned are Google App Engine (GAE) and AWS. The document also questions whether Business Application as a Service (BAE) could be a potential new cloud model.