Drawing programs—such as Adobe Illustrator—are used to create vector graphics, often sometimes called vectordrawings. Vector graphics are drawn mathematically, using lines and curves, rather than the fixed dots used in bitmaps. The Immediate advantage of this format is that the files are generally much smaller than bitmap images, and therefore don’t take as long to print. But the advantages are much greater than that…
First, though, let’s talk a little more about what vector graphics are. At one time there were several vector “draw” programs, but the only real survivor on the professional graphics software side is Adobe Illustrator. Illustrator’s AI file format is essentially Encapsulated PostScript (EPS), a very versatile printer language used primarily in laser proofing machines, imagesetters, and printing presses.
Unlike bitmap images, such as BMP, GIF, JPEG, and PNG, vector graphics don’t consist of groups of dots. Instead, vector graphics are made up of Bezier paths. Paths are defined by a start and end point, along with several other points (also known as Bezier curves), and angles along the way. Paths can be lines, squares, triangles, or…well, squiggly shapes. Paths can be used to create the simplest of drawings or the most complex of diagrams. Paths can also be used to define the characters of particular typefaces.
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