Get The version of installed powershell

$Host.Vesion

• Workflow
  Windows PowerShell Workflow lets IT Pros and developers apply the benefits of workflows to the automation capabilities of Windows PowerShell. Workflows allow administrators to run long-running tasks (which can be made repeatable, frequent, parallelizable, interruptible, or restart-able) that can affect multiple managed computers or devices at the same time.
• Disconnected Sessions
  PowerShell sessions can be disconnected from the remote computer and reconnected later from the same computer or a different computer without losing state or causing running commands to fail.
• Robust Session Connectivity
  Remote sessions are resilient to network failures and will attempt to reconnect for several minutes. If connectivity cannot be reestablished, the session will automatically disconnect itself so that it can be reconnected when network connectivity is restored.
• Scheduled Jobs
  Scheduled jobs that run regularly or in response to an event.
• Delegated Administration
  Commands that can be executed with a delegated set of credentials so users with limited permissions can run critical jobs
• Simplified Language Syntax
  Simplified language syntax that make commands and scripts look a lot less like code and a lot more like natural language.
• Cmdlet Discovery
  Improved cmdlet discovery and automatic module loading that make it easier to find and run any of the cmdlets installed on your computer.
• Show-Command
  Show-Command, a cmdlet and ISE Add-On that helps users find the right cmdlet, view its parameters in a dialog box, and run it.

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    <a href="http://blogs.technet.com/b/heyscriptingguy/archive/2012/09/06/powershell-3-0-is-now-available-for-download.aspx" target="_blank">Source </a>
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