SaaS, PaaS and IaaS

SaaS, PaaS and IaaS are the three main types of cloud service, differing in how much the provider manages. IaaS (Infrastructure as a Service) provides virtual machines, storage and networks; you manage the operating system and applications. Examples: AWS EC2, Azure Virtual Machines.

PaaS (Platform as a Service) also manages the operating system and runtime, so you only deploy your code; examples include Heroku, Google App Engine and Azure App Service. SaaS (Software as a Service) is complete software used through a browser, such as Gmail, Microsoft 365 and Salesforce.