cloud agent

Definition

Cloud agent is software that is installed on the cloud server instances in order to provide security, monitoring, and analysis solutions for the cloud. They actually provide information and helps to provide control over cloud entities.
Paraphrased by @henkvancann based on source.
Also see Agent.

Cloud computing

Cloud computing[1] is the on-demand availability of computer system resources, especially data storage (cloud storage) and computing power, without direct active management by the user.
More at source on Wikipedia