Powershell is basically a scripting language. It is an Object Oriented Programming language and interactive command line shell for Microsoft Windows. This scripting language can be used for various tasks like -
1> System administration
2> Automation of tasks.
3> allows you to work on Active Directory, Exchange Server, Windows Servers, SQL servers, Sharepoint Servers and other Microsoft Office Suites.
It involves and integrates with .NET environment and can also embed into other applications with ease.
Below are the few links which you should try if you want to learn powershell.
PowerGUI.org gives you a UI based powershell scripting environment with Intellisense that makes scripting more enjoiable rather than seeing a broing blue screen command prompt.
I started using powershell recently and have adapted to it very quickly provided my very less exposure to hard core coding.
I had installed the Powershell Script Editor from PowerGUI.org and wnet through the ebook present in http://powershell.com/ .
With these two in your hand, you are ready to rock and roll POWERSHELL.. Happy Learning... :)