Infrastructure is a term used to denote components of the cloud such as servers, storage, databases, networking, etc. In order to run applications in the cloud, you need to provision the appropriate infrastructure to do so. The major cloud providers offer Infrastructure as a Service, which is a one-stop shop for picking and choosing the infrastructure you need to build your cloud applications.
What do we mean by this?
The roads, highways, side streets, parks, and public transportation of the internet.