Basics

Code	Explanation
Get-Command	Retrieves a list of all the commands available to PowerShell
(native binaries in $env:PATH + cmdlets / functions from PowerShell modules)
Get-Command -Module Microsoft*	Retrieves a list of all the PowerShell commands exported from modules named Microsoft*
Get-Command -Name *item	Retrieves a list of all commands (native binaries + PowerShell commands) ending in "item"
Get-Help	Get all help topics
Get-Help -Name about_Variables	Get help for a specific about_* topic (aka. man page)
Get-Help -Name Get-Command	Get help for a specific PowerShell function
Get-Help -Name Get-Command -Parameter Module	Get help for a specific parameter on a specific command