Photography is an art. Done with intention, the process allows an individual to see a scene within their minds eye, then set about to create that image. From a technical aspect this means setting up the camera and lighting in a manner that helps create that image within the camera.
Imagine standing at the edge of the beach where the ocean ebb and flow brings water nearly to your feet. In and out the water flows in sets. Each wave has energy and action but some waves are bigger than the others. As one wave comes in, it splashes on the rocks and rolls onto the sand and as it is receding is met with the incoming wave.
One photographer might be see the scene and be inspired to stop the action and capture the water drops in the air as they smash on the lava rocks. Accordingly they will set their camera with a fast shutter speed and high F-stop. Another photographer might just be overcome with the natural beauty of the scene and take a picture, not really thinking about depth of field or how motion might affect the emotion of the portrait.
A third photographer might see how the water flows and visualize it coming in slow so it creates a silky sheen. Accordingly, that photographer might use neutral density filters and ISO, to manage the light in order to use a slow shutter speed and get the desired affect in the camera. If you want to learn more about photography consider a private workshop.