Types of graphics

Computer graphics are pictures and drawings produced by computer.

There are two main categories:

• Raster graphics - represent images as bitmaps; they are stored as a collection of pixels. The density of dots is known as a resolution (in dots per inch) and determines how sharp the image is. When a picture is scaled up, the number of pixels stays the same, they move apart and the image can become distorted. Popular raster formats are JPEG, GIF and TIFF. This software is used in digital cameras.
• Vector graphics represent images through the use of geometric objects, such as lines, curves and polygons, based on mathematical equations. They are expressed in a vector format, so they have a starting point, a length and a direction. They are easy to change or enlarge without any loss of resolution. When a vector graphics image is enlarged, the number of pixels used to make up the image increases in proportion, so the detail remains the same. It is ideal for high-resolution output.