All the flavors!

Windows XP Home Edition For home users, Personalized Welcome Screen, fast user switching
Windows XP Professional

Windows XP Professional 64bit

For corporate users. 2 processors, 4GB memory
Windows XP Embedded For PDA, and Thin Clients (Windows-based Terminals)
Pocket PC 2002 OS for PDA's
Windows XP Tablet PC For cool Tablet PC released in november 2002
Windows XP Media Center XP with special media capabilities: TV, DVD recording, special Media Player GUI
Windows Server 2003 Standard Edition Small and medium server solutions: Supports 2 processors, 4GB memory.

Note: win2k Advanced server supports 4 processors!
Terminal Server only in Admin mode!

Windows Server 2003 Enterprise Edition

Windows Server 2003 Enterprise 64 bit (already available! as LE (Limited Edition)

Business Critical Servers: Supports 8 processors, 8 GB memory, 2 node Clustering, 32 node Network Load balancing
Terminal Server application mode
Windows Server 2003 Data Center Edition

Windows Server 2003 Data Center 64bit Edition

Mission critical High availability: 32 processors, 64 GB, 4 node clustering, 32 node Network Load Balancing, Winsock Direct
Windows 2003 Server Web Edition Stripped down server for web server use only
Windows 2003 Appliance Edition Like in NAS 3.0 based on Windows 2003 with enhanced storage features and tuning
Windows 2003 Terminal Server Not a separate edition but standard and enterprise can run in Terminal server mode
Windows 2003 Small Business Server Multi Purpose server for small business

New Windows release schedule: last update: 22-03-2003

NT 5.1

NT 5.2

Whistler Beta 1 October 23 2000 Whistler Beta1 October 31 2000
Whistler becomes Windows XP February 5 2001    
Windows XP Beta 2 March 25 2001 Whistler Beta 2 March 23 2001
Windows XP RC1 June 30 2001 Windows .NET 64bit LE August 2001
Windows XP RC2 July 28th 2001 Windows .NET Beta3 November 2001
Windows XP RTM Friday August 24th 2001 Windows .NET build 3615
Windows XP in stores October 25th 2001 Windows .NET build 3621 April 26th 2002
Windows XP Embedded December 2001 Windows .NET RC1 July 24 2002
Windows XP SP1 September 9 2002 Windows .NET RC2 December 5 2002
Windows XP Tablet PC November 2002 Windows .NET name change Windows 2003 January 9 2003
    Windows 2003 RTM March 28 ? 2003
Windows XP Media Center      
    Windows 2003 in stores April 24th 2003
    Windows 2003 SBS  
Other OS'es   NAS 3.0  
Pocket 2002 October 4th 2001    
Smartphone 2003    

Longhorn (NT6.0)

Blackcomb (NT7.0)

These dates are wild guesses...

Beta1 q4 2003 Beta1 Late 2005
RTM 2005 RTM Late 2007/early 2008