This page shows four views of a piece of DNA with 12 nucleotides in each strand. 
       Upper left: stick model                          
       Upper right: spacefill model
       Lower left: bases in sticks, backbone in spacefill
       Lower right: bases in spacefill, backbone in sticks -- Notice how the base pairs are in close contact with each other, so that they interact with each other through London (van der Waals) forces.

The color code is:
    carbons on strand 1 = white               adenine = blue
    carbons on strand 2 = magenta         guanine = green
    oxygens = red                                       cytosine = red
    phosphorus = yellow                           thymine = cyan (light blue)