Raster and vector images

Raster Images
Raster images are images which when you zoom in you can see each pixel. When you do this you then can get the colour value of each pixel using the red , green and blue scale. You can see it in this picture for example.Raster images usually use jpg , tiff , png ,psd and bmp file formats to save them to.

The problem with raster images is that the resolution is set. You cant scale it to a different size without a loss of quality. This is the complete opposite to vector images as they scale easily. They main use for raster images is photographs and photo-realistic images. Devices such as camera's and scanners produce a raster image since an image editor will work on pixels.


Vector Images
Vector images are mad up of paths and stokes. vector images are good because they keep their quality even if you zoom in. This is because vector images can be scaled to any size without loss of quality since raster are based on pixels and vector images arn't. The file formates vector images use though are normally wmf , psd , fla and ai.

Another advantage about vector images are that no matter what resolution the image is , it will always be the same file size which doesn't really matter any more since there's hard drives with terabytes of space now. For a vector image to be displayed or printed the device has to convert it into raster format before its able to render it.