Hello, Graphics-Creators of RSBandB.
I have created this post as I have in the past and present seen bitmap images incorrectly titled as being vectors. I will further definate the differences between the two in the remainder of this post.
What exactly is a vector?
A vector graphic is a graphic created in a vector graphic program such as Illustrator, Macromedia Flash or Inkscape. Vector graphics are rendered by mathematical formulas rather than pixels as is the case with bitmap graphics. As such, Vectors can be rescaled indefinitely without any adverse effects toward image quality.
What is a bitmap?
A raster graphic, or bitmap, is a graphic created in a raster graphic program such as Paint, Photoshop or The Gimp. Raster graphics consist of little squares called pixels to render the image.
Now, it seems that it is commonly, though incorrectly, viewed that an image that contains random shapes or silhouettes of objects is a vector. However, this is not the case as generally the image was not created in a vector graphics program and cannot be resized without pixelation.
Instead, this image can be referred to as a Vexel
As seen in the wikipedia article, a vexel is a raster image that imitates the vector graphics style. Though the "vector graphics style" normally consists of more than random shapes and silhouttes, this is the closest definition that there is to these types of graphics pieces.
One last note:
Though vector images created in a vector graphics editor but saved as raster files technically aren't vectors as they are now raster. It is, in my opinion, acceptable to publicize the bitmap image as a vector as long as you save a vector version as well. This is due to the fact that Internet Explorer does not support the internet accesable filetype of Scalable Vector Graphics or SVG.