ontainers as a service (CaaS) is a cloud service model that allows users to upload, organize, start, stop, scale and otherwise manage containers, applications and clusters. It enables these processes by using either a container-based virtualization, an application programming interface (API) or a web portal interface. CaaS helps users construct security-rich, scalable containerized applications through on-premises data centers or the cloud. Containers and clusters are used as a service with this model and are deployed in the cloud or in onsite data centers.

Source: IBM