====== Which SharePoint version do I have installed? ======
There is no easy way to find out what SharePoint 2013 Edition you are running. You can do it by doing one of two things:

  * You have to dig the registry
  * Use PowerShell

Registry method

  * Open Regedit
  * Navigate to HKLM\SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\15.0\WSS\InstalledProducts
  * Compare the guids with the list

PowerShell method

  * Open SharePoint management Shell
  * Type the comment "(Get-SPFarm).Products" (without the quotes)
  * Compate the guids with the list

GUIDS:

C5D855EE-F32B-4A1C-97A8-F0A28CE02F9C - SharePoint Server 2013
CBF97833-C73A-4BAF-9ED3-D47B3CFF51BE - SharePoint Server 2013 Preview
B7D84C2B-0754-49E4-B7BE-7EE321DCE0A9 - SharePoint Server 2013 Enterprise
298A586A-E3C1-42F0-AFE0-4BCFDC2E7CD0 - SharePoint Server 2013 Enterprise Preview
D6B57A0D-AE69-4A3E-B031-1F993EE52EDC - Microsoft Office Web Apps Server 2013
9FF54EBC-8C12-47D7-854F-3865D4BE8118 - SharePoint Foundation 2013
35466B1A-B17B-4DFB-A703-F74E2A1F5F5E - Project Server 2013
BC7BAF08-4D97-462C-8411-341052402E71 - Project Server 2013 Preview