Find SharePoint Features with PowerShell

if ((Get-PSSnapin -Name "microsoft.sharepoint.powershell" -ErrorAction SilentlyContinue) -eq $null ) {
    Write-Host "Adding SharePoint Snap-in" -ForegroundColor Cyan;
    Add-PSSnapin microsoft.sharepoint.powershell -ErrorAction SilentlyContinue;
} else {
    Write-Host "SharePoint Snap-in already loaded" -ForegroundColor Green;
}

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Write-Host "Get all features in the farm sorted by DisplayName" -ForegroundColor Cyan;
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Get-SPFeature | Sort DisplayName;

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Write-Host "Get a site collection and then all the features in the site collection" -ForegroundColor Cyan;
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Write-Host "List all site collections" -ForegroundColor DarkCyan;
Get-SPSite;

Write-Host "Get a specific site collection and show the features" -ForegroundColor DarkCyan;
$siteCollection = Get-SPSite | where { $\_.Url -eq "http://vm882/sites/cit"};

Get-SPFeature -Site $siteCollection | Sort DisplayName;

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Write-Host "Get a site and then all the features in the site" -ForegroundColor Cyan;
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$site = Get-SPWeb -Site $siteCollection | where {$\_.Url -eq "http://vm882/sites/cit"};
Get-SPFeature -Web $site | Sort DisplayName;