title: What is "date"? "Get-Command date" throws CommandNotFoundException
body: <p><code>date</code> working:</p>
  
  <pre><code>PS&gt; date
  
  Saturday, June 10, 2017 9:10:11 AM
  </code></pre>
  
  <p>But <code>Get-Command date</code> throws exception:</p>
  
  <pre><code>PS&gt; Get-Command date
  Get-Command : The term 'date' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
  At line:1 char:1
  + Get-Command date
  + ~~~~~~~~~~~~~~~~
      + CategoryInfo          : ObjectNotFound: (date:String) [Get-Command], CommandNotFoundException
      + FullyQualifiedErrorId : CommandNotFoundException,Microsoft.PowerShell.Commands.GetCommandCommand
  </code></pre>
  
  <p>Also <code>Get-Alias date</code> throws exception:</p>
  
  <pre><code>PS&gt; Get-Alias date
  Get-Alias : This command cannot find a matching alias because an alias with the name 'date' does not exist.
  At line:1 char:1
  + Get-Alias date
  + ~~~~~~~~~~~~~~
      + CategoryInfo          : ObjectNotFound: (date:String) [Get-Alias], ItemNotFoundException
      + FullyQualifiedErrorId : ItemNotFoundException,Microsoft.PowerShell.Commands.GetAliasCommand
  </code></pre>
  
  <p><code>$PSVersionTable.PSVersion</code> is "5.1.15063.296" on Windows 10.</p>
  
  <p>The <code>date</code> seems not to be a cmdlet, function, script file, operable program or alias. So, what is the <code>date</code>?</p>