Download and Install Terraform - Windows (PowerShell)

downloadTerraform.ps1

[CmdletBinding(DefaultParameterSetName='Version')]
param
(
    [Parameter(ParameterSetName='Latest', Mandatory = $true)]
    [Parameter(ParameterSetName='Version', Mandatory = $true)]
    [String]
    $SaveToPath,

    [Parameter(ParameterSetName='Version', Mandatory = $true)]
    [String]
    $Version,

    [Parameter(ParameterSetName='Latest')]
    [Switch]
    $Latest
)

try
{
    if ($PSCmdlet.ParameterSetName -eq 'Version')
    {
        $downloadVersion = $Version
    }
    else
    {
        $releasesUrl = 'https://api.github.com/repos/hashicorp/terraform/releases'
        $releases = Invoke-RestMethod -Method Get -UseBasicParsing -Uri $releasesUrl
        $downloadVersion = $releases.Where({!$_.prerelease})[0].name.trim('v')
    }

    $terraformFile = "terraform_${downloadVersion}_windows_amd64.zip"
    $terraformURL = "https://releases.hashicorp.com/terraform/${downloadVersion}/${terraformFile}"

    $download = Invoke-WebRequest -UseBasicParsing -Uri $terraformURL -DisableKeepAlive -OutFile "${env:Temp}\${terraformFile}" -ErrorAction SilentlyContinue -PassThru

    if (($download.StatusCode -eq 200) -and (Test-Path "${env:Temp}\${terraformFile}"))
    {
        # If SaveToPath does not exist, create it
        if (-not (Test-Path -Path $SaveToPath))
        {
            $null = New-Item -Path $SaveToPath -ItemType Directory -Force
        }

        # Unblock File
        Unblock-File "${env:Temp}\${terraformFile}"

        # Unpack archive
        Start-Sleep -Seconds 10
        Expand-Archive -Path "${env:Temp}\${terraformFile}" -DestinationPath $SaveToPath -Force

        # Clean up temp folder
        Remove-Item -Path "${env:Temp}\${terraformFile}" -Force

        # Set up environment variable
        $path = [Environment]::GetEnvironmentVariable('Path','User')
        [Environment]::SetEnvironmentVariable('PATH', "${path};${SaveToPath}", 'User')
    }
}
catch
{
    Write-Error $_
}

Hi Rama Krishna, this script is not working

What have you tried?
.\downloadTerraform.ps1 -SaveToPath C:\Terraform -Latest worked for me.