Software as a service, sometimes referred to as "on-demand software" supplied by ISVs or "Application-Service-Providers" (ASPs), is a software delivery model in which software and associated data are centrally hosted on the cloud. SaaS is typically accessed by users using a thin client via a web browser. SaaS has become a common delivery model for many business applications, including Office & Messaging software, DBMS software, Management software, CAD software, Development software, Virtualization ,accounting, collaboration, customer relationship management (CRM), management information systems (MIS), enterprise resource planning (ERP), invoicing, human resource management (HRM), content management (CM) and service desk management. SaaS has been incorporated into the strategy of all leading enterprise software companies. One of the biggest selling points for these companies is the potential to reduce IT support costs by outsourcing hardware and software maintenance and support to the SaaS provider.
Major areas include: Platform/Operating Systems, Application Software, and Enterprise Software (CRM, ERP, and SCM)