Windows 8.1

Windows 8.1 is an operating system released by Microsoft in 2013. For pre-release wallpapers, see Windows 8.1 Preview.

Wallpapers
While Windows 8.1 reused the Flowers theme from Windows 8, it came with a new default wallpaper and replaced the Nature theme with the Lines and colors theme. It is not known where most of the wallpapers from this theme originate from, although one of them is known to be an altered photo from Getty Images. The others could also come from Getty, although reverse search engines regard them as too simplistic to make a match.

Lock Screen Wallpapers
8.1 came with a few built-in lock screen wallpapers, some of which came from Getty Images, while the others were created by Microsoft themselves, including graphic designer Marius Bauer. Most of these were reused from 8.

User Account Pictures
Windows 8.1 has only 2 absolutely identical user account pictures, user and guest, used for default accounts and guest account respectively. Both of them were reused from Windows 8.

They have very high (comparing to used in Windows versions before Windows 8) resolution of 448x448px. Also it has .png versions and resized versions of these images, probably used by Metro applications.

Picture Password
You can see this image in the Picture Password setup tutorial when setting it for the first time: