In Large Format Printing (LFP) vectors are very important. As they allow us to create large graphics that are crisp and well defined. Have you ever seen a photo blown up that was very messy looking? More than likely, it was a bitmap image, or a jpg blown up more than it should have been.
A bitmap image (jpg, png, bmp) is an image made up of individually colored pixels (or squares of color). All bitmap images have a resolution or number of pixels per inch. Most internet images are 72 pixels per square inch. A high resolution image is at least 300 pixels per inch or many more. The problem with high ppi images is they take up much more room on a computer and also slow down computer speeds. Rarely are images which are large and also high resolution placed on the internet. Most point and shoot cameras take images at 144 ppi unless they are set to RAW which takes the largest resolution image the camera allows. High end camera's take higher resolution images.
A vector image (eps, some pdf's, ai, cdw and others) are vector images. A vector is a specific point on a layout. Vector art is drawn using lines from one vector point to another. The resulting shape is then filled with specific colors, patterns, or gradients. The resulting image can be scaled as large or small as possible and still be a high quality image since pixel's aren't involved in the creation of the image.
We frequently ask clients for an eps of their logo or a higher resolution or larger digital image so that we can create the best quality finished product for our clients.