What is the difference between vector and raster images?
A vector image is constructed as a collection of abstract mathematical shapes, and these shapes preserve their identity when you scale the image or add or delete a shape. So, a vector image is resolution-independent. But rendering the image on a screen or a raster printer (both laser printers and ink-jet printers are raster printers) requires calculating an equivalent bitmap, which is slow. Vector images are usually easier for pen plotters to work with, though, and it’s much easier to find a pen plotter which can handle a 24″ x 36″ sheet than a laser-printer of the same size. A raster image is an array of color values, one for each pixel (dot) in the image, so it can be displayed or printed directly on a screen or raster printer that has a corresponding dot spacing. But scaling the image to a different dot spacing (resolution) requires a lot of calculation and is inherently inaccurate: you have to interpolate between existing dot values.
A vector image is constructed as a collection of abstract mathematical shapes, and these shapes preserve their identity when you scale the image or add or delete a shape. So, a vector image is resolution-independent. But rendering the image on a screen or a raster printer (both laser printers and ink-jet printers are raster printers) requires calculating an equivalent bitmap, which is slow. Vector images are usually easier for pen plotters to work with, though, and it’s much easier to find a pen plotter which can handle a 24″ x 36″ sheet than a laser-printer of the same size. A raster image is an array of color values, one for each pixel (dot) in the image, so it can be displayed or printed directly on a screen or raster printer that has a corresponding dot spacing. But scaling the image to a different dot spacing (resolution) requires a lot of calculation and is inherently inaccurate: you have to interpolate between existing dot values. If you scale up enough to see the original dots
