Windows Server

Windows Server is a family of server operating systems by Microsoft. While Windows NT 3.1 to 2000 had server editions, Windows Server 2003 would be the first to be released under a separate brand name from its client counterpart.

Windows Server 2003 and 2003 R2
Windows Server 2003 is a server operating system released by Microsoft in 2003. It is considered the server counterpart of Windows XP, although it introduces additional kernel improvements. It does not have a default wallpaper, although it does have a branding wallpaper, which is similar to XP's but features a grey background and uses the Server 2003 wordmark instead. Microsoft would release a slightly updated version titled Windows Server 2003 R2 in 2005. The branding wallpaper is identical save for the logo being changed to reflect it being R2.

Windows Home Server
Windows Home Server is a home-oriented version of Server 2003 released in 2007. It features a completely different branding wallpaper that resembles auroras present in Windows Vista; unlike in Server 2003, this is set as the default wallpaper.

Windows Server 2008
Windows Server 2008 is a server operating system released by Microsoft in 2008. It is the server counterpart of Windows Vista. Like Server 2003 and earlier versions, it does not have a default wallpaper, although it features a grey aurora branding wallpaper designed by Frank Bisono titled server. Oddly it is at 800x600, unlike Vista's 1920x1440/1920x1200 wallpapers. The wordmark and logo is placed in roughly the same spot as 2003's wallpaper.

Windows Server 2008 R2
Windows Server 2008 R2 is a server operating system released by Microsoft in 2009. It is the server counterpart of Windows 7. Its branding wallpaper is similar to that of Server 2008, although this time it is widescreen and the logo is smaller. Microsoft would go on to release Windows Home Server 2011 in 2011, a home-oriented version. While it features a different background color, the branding wallpaper is identical to Server 2008 R2's.

Windows Server 2012 and 2012 R2
Windows Server 2012 is a server operating system released by Microsoft in 2012. It is the server counterpart of Windows 8. It features a very minimalistic branding wallpaper, which is simply dark grey with a small white Server 2012 wordmark on the bottom right corner. It is the first server version since Home Server to have this set as the default wallpaper. The following year, Microsoft released Windows Server 2012 R2, the server counterpart of Windows 8.1. Its branding wallpaper is very similar, except featuring an even darker gray and the wordmark reflects it being Server 2012 R2.

Windows Server 2016 and 2019
Windows Server 2016 is a server operating system released by Microsoft in 2016. It is the server counterpart of Windows 10. It features the same default wallpaper as 10. Two years later, Microsoft released Windows Server 2019, featuring the same wallpaper.