Research suggests that for certain kinds of tasks, images combined with text are the most effective means of information transfer. You can illustrate your concept with diagrams, photos, maps, or a variety of other visual resources. Visual resources posted to a Web site are also available 24 hours a day so students who need extra review of material can access it at their convenience. Graphics add color and visual interest to Web pages and PowerPoint presentations . They break up plain text and communicate information pictorially.
Graphics can also unify the look and feel over a series of Web pages or slides.
Digital images are classified as either raster or vector. Raster images, also called bitmapped images, are made up of individual bits or pixels of information placed on a grid. Vector images, also called object-oriented images, are made up of points on a coordinate system thay defines straight lines, curves, and type as mathematically determined outlines. Raster Raster images are resolution dependent. As it is enlarged it gets fuzzy.