Software as a service (SaaS) is a software delivery model providing access to applications through the internet as a web based service. It provides a means to free users from complex hardware and software management by offloading tasks to third parties, who build applications accessible to multiple users through a web browser.
In this scenario, the consumers needs to neither install anything on their premises nor have to pay upfront costs to purchase the software and the required licenses. In other words SaaS or Software as a service basically refers to any of the cloud services through which the users or consumers are able to access applications and software applications on the internet.
SaaS is accessed by users through web browsers. SaaS ranges from database management software, payroll software, management systems, virtualisation, and Enterprise Resource planning, human resource management and so on. SaaS services do not have a high permanent licensing cost as traditional software but instead they generally have a subscription fee or a monthly fee.
Some SaaS applications are also free thereby making it far more useful than traditional software services.
SaaS models can be basically of two types. One is the hosted application management model. This model bears a resemblance to application service provider. Here the SaaS providers host software for their customers, especially those which are available commercially and therein make it available through the Web.
There is one more model for SaaS, where software is provided as per demand. In this model of SaaS, SaaS services are provided network based accessibility to the consumers that is a single copy of the application, which is specifically created for distribution.