HCL Basics
Terraform configuration is written in HCL (HashiCorp Configuration Language).
A configuration is just one or more .tf files made of blocks.
A block has a type, zero or more labels, and a body of key = value
arguments:
block_type "label_one" "label_two" {
argument = "value"
}
hclprovidersterraform-validate
Interview prep
The basics interviewers expect you to state crisply.
What does terraform validate check — and what does it NOT?
validate confirms the configuration is syntactically valid and internally consistent (references resolve, argument types line up), entirely offline. It does NOT contact a provider, read state, or tell you what will change — that's plan.
What is a Terraform provider?
A plugin that maps Terraform resources onto a platform's API — hashicorp/aws knows how to create/read/update/delete AWS resources. The required_providers block declares which providers (and version constraints) a configuration needs.