Explanation
The variable declaration can also include a default argument.
Reference: https://www.terraform.io/docs/language/values/variables.html

Explanation
The remote backend can work with either a single remote Terraform Cloud workspace, or with multiple
similarly-named remote workspaces (like networking-dev and networking-prod). The workspaces block of the
backend configuration determines which mode it uses: To use a single remote Terraform Cloud workspace, set
workspaces.name to the remote workspace's full name (like networking-prod). To use multiple remote
workspaces, set workspaces.prefix to a prefix used in all of the desired remote workspace names. For example,
set prefix = "networking-" to use Terraform cloud workspaces with names like networking-dev and
networking-prod. This is helpful when mapping multiple Terraform CLI workspaces used in a single
Terraform configuration to multiple Terraform Cloud workspaces.

Explanation
The current implementation of Terraform import can only import resources into the state. It does not generate
configuration. A future version of Terraform will also generate configuration.
Because of this, prior to running terraform import it is necessary to write manually a resource configuration
block for the resource, to which the imported object will be mapped.
Source: https://www.terraform.io/cli/import

Explanation
The terraform refresh command is used to reconcile the state Terraform knows about (via its state file) with
the real-world infrastructure. This can be used to detect any drift from the last-known state, and to update the
state file.
This does not modify infrastructure, but does modify the state file. If the state is changed, this may cause
changes to occur during the next plan or apply.
https://www.terraform.io/docs/commands/refresh.html

Reference: https://www.terraform.io/docs/cli/commands/init.html