Bitmapped Font, Bitmap Font: A character FONT in which each individual letter form is stored as a table of PIXELS (a picture), in contrast to an OUTLINE FONT where each character is stored as a set of lines or strokes (a description of how to draw the character). Bitmapped fonts are fast and easy to RENDER onto a screen or printer - by simply copying the bits for the character - and for this reason were preferred on older computer systems (up to and including MS-DOS PCs) that used CHARACTER-BASED displays.
Bitmapped fonts render correctly only at the size they were created: to enlarge or reduce their characters involves duplicating or removing pixels, which gives the letters an unattractive jaggy appearance. In contrast, outline fonts can be scaled to any size (above a minimum) with little loss of quality and hence they have almost entirely displaced bitmapped fonts, except for applications such as instruments and hand-held computers with small fixed-size displays. Examples of bitmapped fonts include the fixed-pitch Courier and MS Serif fonts supplied with Windows.
All fonts (typefaces) that you see on the screen are bitmapped. That's the only way the computer can display the typeface on the screen, since the screen is composed of dots (pixels). Some fonts have no other information to them than the bitmapped display you see on the screen, while other fonts have additional data that is used by the printer to print the typeface smoothly on a page (outline, or scalable fonts).