We are accustomed to the way that landscapes look during the day or through the dark dim light of moonlight. With photography, we can extend this look, making dim dark moonlit landscapes look bright as day.
Interesting and beautiful things occur. Stars, which we see as fixed objects in the sky, become streaks traveling towards a destination. Cars disappear, leaving only light trails as evidence of their passing. People disappear. Choppy oceans become flat as glass
Colors that your brain filters out appear. Dim yellow sodium vapor lamps and greenish mercury vapor lamps create a brilliant colorful landscape.
My photographs tend to be mostly unprocessed. As with any quality image, it is impossible to avoid some level of manipulation -- usually adjusting color balances and toning slightly, a little bit of cropping, dust removal, etc.
However, I will note with pride that all of the unique effects I've achieved have been accomplished by careful understanding and control of the light and camera, not through later editing in any sort of software package.