Windows PowerShell® 5.0 includes significant new features that extend its use, improve its usability, and allow you to control and manage Windows-based environments more easily and comprehensively.
Windows PowerShell 5.0 is backward-compatible. Cmdlets, providers, modules, snap-ins, scripts, functions, and profiles that were designed for Windows PowerShell 4.0, Windows PowerShell 3.0, and Windows PowerShell 2.0 generally work in Windows PowerShell 5.0 without changes.
Windows PowerShell 5.0 is installed by default on Windows Server® Technical Preview and Windows 10® Technical Preview. To install Windows PowerShell 5.0 on Windows Server 2012 R2, Windows 8.1 Enterprise, or Windows 8.1 Pro, download and install Windows Management Framework 5.0 Preview. Be sure to read the download details, and meet all system requirements, before you install Windows Management Framework 5.0 Preview.