Vector art or vector format is a term used to describe artwork made with illustration software like Adobe Illustrator and CorelDraw. Vector graphics are created with mathematical formulas as opposed to raster or bitmap images that are made from colourised pixels.
Raster or bitmap images pixelate and look “jaggy” when enlarged. Vector artwork on the other hand can be enlarged to any size without affecting the quality and appearance of the image.
Some of the common vector file formats include .ai (Adobe Illustrator), .cdr (CorelDraw), and .svg (Scaleable Vector Format – used for web images).
Read more on vector file formats.