Software-as-a-service (SaaS) is an on-demand, cloud-based software delivery model that enables organizations to subscribe to the applications they need without hosting them in house. SaaS is one of several categories of cloud subscription services, including platform-as-a-service and infrastructure-as-a-service.
SaaS has become increasingly popular because it saves organizations from needing to purchase servers and other infrastructure or maintain an in-house support staff. Instead, a SaaS provider hosts and provides SaaS security and maintenance to their software. Some well-known SaaS applications include Microsoft Office 365, Salesforce.com, Cisco Webex, Box, and Adobe Creative Cloud. Most enterprise software vendors also offer cloud versions of their applications, such as Oracle Financials Cloud.