Powershell - An intro

Writing a line to the Terminal

1echo "Hello World!"

1Write-Host "Hello World!"

In PowerShell, commands are called CmdLets (pronounced Command-lets). They are given a ‘Verb’-‘Noun’ format. For example: Get-Date, Write-Host.

Get-Command will output all available CmdLets. You can also get a filtered command list by passing it the verb as an argument to the -Verb flag. For example: Get-Command -Verb Get. Usually the verbs are pretty self-explanatory. For example: Get, Remove, Install, Rename, Set and so on..

PS /Users/aamnah> Get-Command -Verb Rename

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Cmdlet          Rename-Item                                        7.0.0.0    Microsoft.PowerShell.Management
Cmdlet          Rename-ItemProperty                                7.0.0.0    Microsoft.PowerShell.Management

Similarly, you can filter by noun. For example: Get-Command -Noun Host

PS /Users/aamnah> Get-Command -Noun Host

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Function        Clear-Host                                                    
Cmdlet          Get-Host                                           7.0.0.0    Microsoft.PowerShell.Utility
Cmdlet          Out-Host                                           7.3.6.500  Microsoft.PowerShell.Core
Cmdlet          Read-Host                                          7.0.0.0    Microsoft.PowerShell.Utility
Cmdlet          Write-Host                                         7.0.0.0    Microsoft.PowerShell.Utility

Keep in mind that not all command are available on all operating systems. PowerShell on Windows will always have more commands available than PowerShell on macOS. For example, a basic one that is available on Windows is Get-ComputerInfo is unavailable on macOS

macOS:

PS /Users/aamnah> Get-ComputerInfo         
GetComputerInfo: The term 'Get-ComputerInfo' is not recognized as a name of a cmdlet, function, script file, or executable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

You can check how many commands for a particular verb are available for your OS with the following command

1Get-Command -Name Get* | Measure-Object

• Clearing the screen output can be done with cls, clear or Clear-Host
• Find out PowerShell version with $Host.version or $PSVersionTable