Why do you require vector images?

Vector images are made out of lines and shapes. This helps us when we need to separate colours. Each shape that has the same colour is separated from the image. This can’t effectively be done with a bitmap image when printing with spot colours.

One time when it is ok to use bitmap images is when you want a full colour print using process CMYK colours. Sometimes bitmap images are ok for single colour prints as long as they are at least 300dpi and already at print size.