Say, you need to quickly find out the version of SQL server and the operating system running on a computer.  You could, execute ver from command prompt to get the version of Windows operating system, e.g. Microsoft Windows [Version 6.0.6000].  Then, to get the SQL Server version, you could run select @@version from SQL Management Studio and get something like Microsoft SQL Server 2005 - 9.00.2047.00 (Intel X86)   Apr 14 2006 01:12:25   Copyright (c) 1988-2005 Microsoft Corporation  Developer Edition on Windows NT 6.0 (Build 6000: ) or just click on Help -> About (in SQL Management Studio) and get something like:

Microsoft SQL Server Management Studio             9.00.2047.00

Microsoft Analysis Services Client Tools                2005.090.2047.00

Microsoft Data Access Components (MDAC)          6.0.6000.16386 (vista_rtm.061101-2205)

Microsoft MSXML                                                 3.0 5.0 6.0

Microsoft Internet Explorer                                  7.0.6000.16386

Microsoft .NET Framework                                   2.0.50727.312

Operating System                                               6.0.6000


Or, you can use an extended stored procedure xp_msver that returns version info, plus processor type, physical memory, and more (see below).  The beauty of this option, is that you can execute it via sqlcmd utility from the command prompt!

Index  Name               Internal_Value           Character_Value

1          ProductName     NULL                             Microsoft SQL Server

2          ProductVersion   589824                         9.00.2047.00

3          Language          1033                             English (United States)

4          Platform            NULL                             NT INTEL X86

5          Comments         NULL                             NT INTEL X86

6          CompanyName  NULL                             Microsoft Corporation

7          FileDescription   NULL                             SQL Server Windows NT

8          FileVersion         NULL                             2005.090.2047.00

9          InternalName     NULL                             SQLSERVR

10         LegalCopyright   NULL                            © Microsoft Corp. All rights reserved.

11         LegalTrademarks           NULL                 Microsoft® is a registered trademark of Microsoft Corporation. Windows(TM) is a trademark of Microsoft Corporation

12         OriginalFilename            NULL                 SQLSERVR.EXE

13         PrivateBuild       NULL                             NULL

14         SpecialBuild       134152192                    NULL

15         WindowsVersion 393216006                    6.0 (6000)

16         ProcessorCount  2                                  2

17         ProcessorActiveMask      3                      00000003

18         ProcessorType   586                               PROCESSOR_INTEL_PENTIUM

19         PhysicalMemory 2047                             2047 (2146041856)

20         Product ID         NULL                             NULL