Vector graphics rendering, sometimes abbreviated VML, refers to scalable vector graphics (SVG) used in Web pages. This feature came into widespread use with Microsoft Internet Explorer version 5.
Vector graphics formats offer advantages over traditional bitmap formats such as GIF or JPG. Perhaps most significant is the fact that with certain types of imagery, vector graphics files are much smaller, in terms of the number of bytes they contain, than bitmap files of the same objects with similar detail. This makes Web pages load faster. Another asset of vector graphics is the fact that they can be easily scaled without loss of image resolution.
Vector graphics rendering is best suited to images in which shapes can be defined by mathematical functions (for example, straight lines, simple curves, waves, circles, ellipses, squares, rectangles, and triangles). In some situations, vector graphics are inferior to bitmap graphics. An example is a photograph of a complex nature scene including trees, clouds, and other objects with fractal features. While it is possible to render such an image in vector format, the vector file may contain several times as many bytes as the equivalent bitmap file.