Graphics on a screen are made up of tiny blocks called pixels. The more pixels on the screen, the higher the resolution and the better the quality of the picture will be. The higher the image resolution, the more memory is needed to store the graphic.
Bitmap images are organised as a grid of coloured squares called pixels (short for 'picture elements'). When zooming in or enlarging a bitmap image, the pixels are stretched and made into larger blocks. This is why bitmap images appear as poor quality when enlarged too much.
Each colour of an image is stored as a binary number. In the black-and-white image below, each pixel is either black or white. You need a binary value for each different colour. As each pixel is either black or white, this image can be encoded with a value of 0 for white and 1 for black.
A vector image uses scalable shapes such as straight lines and curves, using coordinates and geometry to precisely define the parts of the image. It is more efficient than bitmaps at storing large areas of the same colour because it does not need to store every pixel as a bitmap does.
Vector graphics can be scaled without losing resolution. They can be enlarged or reduced in size - but the file size will stay almost exactly the same.
One of the most common vector file formats is scalable vector graphics (SVG). SVG is an open standard for vector graphics.
Vector graphics are used in:
When a monitor or a printer displays a vector image it is rasterised - converted into a grid of pixels. Regardless of the file type, an image will always be outputted onto a screen or printed in pixels.