They're based on a dot-matrix or pixel grid and require a high resolution in order to be printed or adapted to multiple display formats.
It isn’t scalable, if you increase the size of a raster image, this image will look blurry. To prevent this we can only leave the image to its original size or downsize.
Allows the user to keep the quality of their design across multiple formats and resolutions. In a vector file, each point, line, and shape created is fully scalable.