Need help to understand Powershell code.

Hi,

Is someone can tell me what is the difference between "Get-ADUser User -Properties UserPrincipalName | select SamAccountName,UserPrincipalName" and ""Get-ADUser User | select SamAccountName,UserPrincipalName" because I got same result when I export it to csv:

1)
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$SamAccount = Import-Csv "C:\SamAccountName.csv"

$SamAccount | % {Get-ADUser $_.SamAccountName -Properties UserPrincipalName | select SamAccountName,UserPrincipalName

} | Export-csv "C:\UserPrincialName.csv" -NoTypeInformation
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2)
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$SamAccount = Import-Csv "C:\SamAccountName.csv"

$SamAccount | % {Get-ADUser $_.SamAccountName | select SamAccountName,UserPrincipalName

} | Export-csv "C:\UserPrincialName.csv" -NoTypeInformation
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