Rendering is the process of giving a more realistic look to a computer generated drawing. It's also what you do to beef fat to make lard but that's a different forum.
Here's an example of the first sort of rendering.
There are a number of software applications out there that do rendering. Like anything they have a bit of a learning curve. There is a very nice, fairly easy to use renderer called Kerkythea. It's free which is a good thing. There's a little hangup with the free version of SketchUp, though. It has no native facility for exporting a file that can be opened in Kerkythea (get it here)--or other renderers. There is a solution, however. You can get a Ruby script called SU2KT here: SU2KT ZIP file without lights. or The executable installer with some light fixtures included. This script makes it easy to export your SU model so Kerkythea can open it.
Now there's an even easier albeit somewhat limited way to make a rendered image of your model. It is designed for those who have no experience but want to get that rendered look from their models. This is only a beta version and the final version won't be free. The beta version is limited to 640x480 output but for most things that's not so bad . Go to http://www.suplugins.com/ and download another Ruby script--it comes as an EXE file which you run to install it. Then you can make your render directly in SU. When you open the renderer, called Podium, there's little dialog box. Click on the arrow in the upper right corner and choose Help to get some instructions on how to make it work.
This image was done this morning in about 3 minutes using Podium.
It's not perfect but considering the little bit of time I have invested, I think it turned out alright. Note that I did add a background wall for this version which isn't present in the higher res render done in Kerkythea.
If you're really interested in the other sort of rendering here's a link for that, too. Hey Lardboy!