In a well composed photograph, one of the key components is a strategically placed element in the foreground.
In any scene with several subjects or objects in the front and back of the frame, the foreground elements will catch the eye in the first instant. The eye is then pulled into the rest of the scene, to the middle ground, and then the background, giving the perception of depth. An empty foreground will give an image less impact.
1) Only one of many features in a large depth of field, which is generally the case with landscape, real estate and travel photography;
2) The most prominent feature in the scene with a short depth of field, as it usually is in portraiture, food and macro photography.
Whether you choose to have a wide or shallow depth of field, it's important to include objects or human subjects into the foreground, so the eye doesn't wander:
Image taken by Alex Schwab
Image taken by Dawn Verdaguer
The background should enhance the story you are trying to tell in your photograph, whether it is sharp or blurred. In the photo below, even though the foreground is sharper than the background, it helps to make the message within the photograph much more meaningful.
The quote on the coffee cup ties in with the mother and daughter hugging behind it. Image taken by Katherine Gruender.
After choosing a feature to include in the foreground, try these tips to get different effects:
Getting down close to the ground can magnify the prominence of the object or subject. Experiment with various viewpoints, depending on the size of your foreground element.
Find the beginning of a leading line in the foreground that extends into the background, to draw the eye further in.
Keep an eye on your horizon. The foreground and background are separated by the horizon, and you can emphasise the foreground by keeping the horizon higher in the frame.