Google has made up some improvement with their search engine. Before this your can refine your image search using their color palette if your want to search images with certain color and also type of image including the images size. The latest updates from Google that we heard is the background images for your default Google search engine page.

You can do this by clicking "change background image" that located at the bottom left of the page. To change this you must have an account with Google and login to change the image. Have a good try!

[Via Google]