Windows allows to change the background with a solid color, photos from your hard drive or images included in the operating system itself. The newer versions of Windows allow to use multiple images as background (wallpaper) and change them automatically at different intervals (seconds, minutes, hours, day).
Also, you can set a background image to fill the entire screen, center it or fit into the screen while preserving the quality of the original image.
Windows 8
Method 1: Using Personalize
1 Go to Desktop
2 Go to Personalize
3 Go to Desktop background
4 Choose the new background
Select Solid Colors if you want to use a color instead of a picture.
5 Set the new background
Then choose the time interval when the pictures will be changes.
Method 2: Directly from an existing picture
You can choose a custom picture (wallpaper) as background from the Personalize menu, but also you can set an image as background through right click.
1 Go to the picture
As you can see, i will set as background the image Desert.jpg
2 Set the image as background
Windows 7
Changing backgrounds in Windows 7 and Windows 8 are similar.
Method 1: Using Personalize
1 Go to Personalize
2 Go to Desktop Background
3 Choose background type and source
Choose a location of pictures from your hard drive if you want an image.
4 Set the background
If you want to change it again, repeat the steps.
Method 2: Using a custom picture
This is a faster way to set a new background, if you want to use a single image from the local hard drive.