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In other words, vector graphics are resolution-independent and thus can remain the highest quality at any scale. Raster images are based on pixels and thus scale with loss of clarity, while vector-based images can be scaled indefinitely without degrading. The former is the representation of images as an array of pixlels, and the latter uses paths, points, lines, curves and shapes or polygons (which are all based upon mathematical equations) for the same purpose.
In computer graphics images can be represented in two ways - using raster graphics (or bitmap) or vector graphics.