Structural information
Vectors contain structural information that bitmap images do not. In the examples above, the components of the vector image can be manipulated separately - while those of the bitmap image cannot. Each point, line and shape in a vector image is specified precisely in mathematical terms. It follows that such elements can be moved and resized separately - and without loss in resolution. On the other hand, a bitmap is simply a flat pixel grid, with no structural information. The only information a bitmap image contains is the colour for each pixel. When it is enlarged, there is no information available about the new pixels created by the enlargement, and a jagged 'staircasing' effect is produced. With a vector, the resizing factor is simply fed into the equation, and the quality of the larger image is identical to that of the original.
Next page: bits