Now to change wallpaper Nikon D40?

Bought my Nikon D40 from a friend as a starter camera, didn't come with booklet.
Read up on the settings, controls, etc.online but couldn't find how to change the wallpaper.

This is annoying, please help.

Added (1). There's a wallpaper, just like computers and cellphones. In the background. It's a picture of the friend who sold me the camera. She doesn't remember how to change it though.

No, I'm not talking about the image previewing.

Look it up. Every site that discusses the Nikon D40 features has mentioned this but hasn't given me the option to change it.

It's ridiculous and reduces image setting display size.

I don't need anyone to tell me that there's no such thing, because there's. And if you aren't familiar with this camera don't give useless answers.

Someone please help.)

Wallpaper like on your telephone or computer?

There's no such thing on a dSLR.

The screen is either black or or shows you the images you have shot and are on your memory card

Change what wallpaper?

Here is a page with a link to download the user manual:
http://support.nikonusa.com/...a_id/14157" class='ext_link'>http://support.nikonusa.com/...a_id/14157
Among my collection of cameras is a Nikon D60, which is similar to the D40. I think there was a feature, which I never bothered trying to use, to put a background image in the LCD information display.

I does have a wallpaper. The best I can do is give you link to a down load version of the manual it's on page 80-82.It's hard to read and to try figure it out without the camera. I wish I could be more of a help.

manual
http://support.nikonusa.com/app/answers/detail/a_id/14157