@komalsinghjadon: Hard to pick a "best" book available, as there are several that are really good.
The one I personally learned from is "Learn Windows PowerShell in a Month of Lunches" by Don Jones. It's not free, but it's a good reference. The "Windows PowerShell Cookbook" by Lee Holmes is another really good book that helped me learn.
If you are seeking free ebooks, you should start by reviewing the list on PowerShell.org/ebooks.
@stahtufiang: Unfortunately, this question can be interpreted multiple ways.
If you are asking - how do you ensure standard (non-admin) users cannot run scripts: you can use Execution Policy to block running scripts, however that can be over-ridden by an administrator. To get information about this feature, run the command "get-help set-executionpolicy -detailed"