If you plan to use lines or waves for PowerPoint presentations, everyone's eyes will be focused on your slideshow. Many presenters use lines in PowerPoint backgrounds. Whether the lines are straight, vertical, or wavy, the focal point will keep those you're presenting to, at the center of the PowerPoint slide. Then the eyes will automatically be directed to other areas of the PowerPoint slide. Ultimately, this is your main goal when presenting to your group of people.
Waves in ppt presentations are also commonly used. The eyes are directed around all areas of the slide. The reader will be able to focus on the text longer while the background is enhanced with color and diversity. For example, perhaps blue waves in ppt presentations with a black background, reminds someone of high speed or technology. Just the way line backgrounds for PowerPoint are placed, will prompt a viewer to think of a particular topic. That is why choosing a certain PowerPoint background may not work for a different topic.
Although choosing waves or lines may not be that simple, either choice will spruce up a PowerPoint presentation. While waves for ppt presentations suggest a "flowing" feeling, the lines also suggest a futuristic style. Experiment with different waves or lines for PowerPoint backgrounds and see which one is a perfect fit for your presentation. Colors will also make a difference in the final outcome of the slide. Using waves or lines in PowerPoint backgrounds will add creativity to your presentation.