SaaS
Software-as-a-Service — software delivered as a managed cloud subscription rather than installed and run by the customer.
SaaS stands for Software-as-a-Service. It refers to software delivered as a managed cloud subscription, where the vendor owns the infrastructure, patching, backups, and upgrades, and the customer accesses the service over the internet. All Dynamics 365 apps — Business Central, Finance, Supply Chain Management, Sales, Customer Service, Field Service, and the rest — are sold primarily as SaaS, hosted on Microsoft Azure. SaaS shifts ERP and CRM from a capital project with multi-year on-premise infrastructure to an operational subscription with continuous updates, but in return constrains customisation to supported extensibility patterns rather than direct database access.