How to view my nikon pictures on my computer?

I downloaded my pictures from my nikon d40 to my computer and i can't view them.help?

Added (1). I don't have the box it came in, and it was taken RAW and JPEG

First some questions:

Did you shoot saving them as JPEG files?
Did you shoot saving them as RAW files?

Did you copy all the image files to a new file folder named for the subject and date?
Can you find them where the computer chose to place them?

Both PC and Apple computers have a JPEG viewer as part of their operating systems, so once you find them, they will be visible

If you did shoot using RAW, you will need to process the RAW files and save them as JPEG files

Most of us who shoot using RAW, actually shoot in RAW + JPEG, edit (sort) using the JPEG files and then only process, the best of the rest, matching RAW files

Jpeg you should be able to see wherever you chose to save them.

If you did shoot RAW mode than you can view them by inserting the software suite disc on your PC and it will install software to transfer the images from your camera and let you view the RAW files