Cheating With Shutter Speed
People often see and try to guess how it was done. "Was it really misty there?" people ask. "Was there a fog rising off the ocean in the early morning?" And the answer, of course, is no and no. There's no fog, and the scene didn't look like this in real life. Instead, what you see is the effect you get when you slow down the shutter speed and capture a lot of wave movement in the same exposure.
Do I feel bad that I'm cheating to create a scene that didn't actually exist when I shot the picture? Not at all. Art is always about interpreting reality, and keep in mind you can get this effect entirely within a single exposure on your camera, with no photo editing necessary. It's no more "fake" than if I underexposed a photo to or changed the aperture to .
Setting Up
To take a photo like this, you should have a camera that lets you choose a long shutter speed, so a digital SLR or a point-and-shoot camera with a shutter priority mode is ideal.