1. Problem
You want to control how you define (or interact with) the visibility of variables, aliases, functions, and drives.
2. Solution
PowerShell offers several ways to access variables.
To create a variable with a specific scope, supply that scope before the variable name:
        $SCOPE:variable = value

To access a variable at a specific scope, supply that scope before [...]

1. Problem
You have a list of items and want to work with each item in that list.
2. Solution
Use the Foreach-Object cmdlet (which has the standard aliases foreach and %)to work with each item in a list.
To apply a calculation to each item in a list, use the $_ variable as part of a calculation in [...]

1. Problem
You have an item (for example, an error record, directory item, or .NET object), and you want to display detailed information about that object in a list format.
2. Solution
To display detailed information about an item, pass that item to the Format-List cmdlet. For example, to display an error in list format, type the commands:
        [...]