Reference: https://www.terraform.io/docs/language/providers/configuration.html

Explanation
Terraform installs providers, initialises source code & modules etc at this stage

Explanation
https://www.terraform.io/cloud-docs/workspaces
"When run locally, Terraform manages each collection of infrastructure with a persistent working directory,
which contains a configuration, state data, and variables. Since Terraform CLI uses content from the directory
it runs in, you can organize infrastructure resources into meaningful groups by keeping their configurations in
separate directories.

Explanation
"The terraform taint command informs Terraform that a particular object has become degraded or damaged.
Terraform represents this by marking the object as "tainted" in the Terraform state, and Terraform will propose
to replace it in the next plan you create." FYI - This command is deprecated. For Terraform v0.15.2 and later,
we recommend using the -replace option with terraform apply instead. For Terraform v0.15.2 and later, we
recommend using the -replace option with terraform apply to force Terraform to replace an object even though
there are no configuration changes that would require it. https://www.terraform.io/cli/commands/taint