You need to make sure that you have space on a slide for the image or illustration. However, there is no space on this slide, so if you were really giving this talk, you would add one or more slides after Slide 4 with illustrations of grids. Clip art is easy to acquire and can be added from the Clip Art Gallery provided with PowerPoint. If the Clip Art Gallery was installed during a standard installation, you will have more than 1,000 images to use in your presentations. It is up to you to decide how appropriate images are for your presentation.
Images are good to use, particularly if they support or further explain ideas.
Yet another type of image that may need to be added is an organizational logo. For example, a logo could be added on the title slide. Although it may not be important to know much about images when placing them in a word processing document, you do need to be aware of two types of images as you use them in presentations with a color background. They can also be created with a paint program, like the one that ships with Windows 95. While the pictures included with Microsoft Office are bitmapped images, most of the clip art collection is vector images.