Nowadays, we use a version control system to manage our code, our tests, and our documentation. Infrastructure-As-Code (IaC) takes the same approach to infrastructure. Say you want to manage a web application cluster, with its load balancers, web and application servers and database servers. Additionally, there could be reverse proxies, caches, key-value pair stores, message queues and NoSQL databases as part of the mix. There would be monitoring daemons and rules to set-up, metric gathering, forwarding sink configurations, log collection daemons, etc. You could have web application deployments which are memory intensive, storage intensive, CPU intensive and / or network intensive.
IaC plays very well with cloud and where part of the provisioning can be done via the cloud-specific tools. The orchestration takes the instances from there and completes the configuration and choreography of the processes.
