Go to the previous , next chapter. This question is not trivial to answer. It's analogous to asking what the difference is between various graphics image file formats. Bitmapped fonts are falling out of fashion as various outline technologies grow in popularity and support.
Bitmapped fonts represent each character as a rectangular grid of pixels.
The bitmap for each character indicates precisely what pixels should be on and off. Printing a bitmapped character is simply a matter of blasting the right bits out to the printer. There are a number of disadvantages to this approach. The bitmap represents a particular instance of the character at a particular size and resolution. It is very difficult to change the size, shape, or resolution of a bitmapped character without significant loss of quality in the image.