A computer font (or font ) is implemented as a digital data file containing a set of graphically related glyphs, characters, or symbols such as dingbats. Although the term font first referred to a set of movable metal type pieces in one style and size, since the 1990s it is generally used to refer to a set of digital shapes in a single style, scalable to different sizes. A font family or typeface refers to the collection of related fonts across styles and sizes.
There are three basic kinds of computer font file data formats:
Bitmap fonts consist of a matrix of dots or pixels representing the image of each glyph in each face and size.
Outline fonts (also called vector fonts) use Bézier curves, drawing instructions and mathematical formulae to describe each glyph, which make the character outlines scalable to any size.
Stroke fonts use a series of specified lines and additional information to define the profile, or size and shape of the line in a specific face, which together describe the appearance of the glyph.Bitmap fonts are faster and easier to use in computer code, but non-scalable, requiring a separate font for each size. Outline and stroke fonts can be resized using a single font and substituting different measurements for components of each glyph, but are somewhat more complicated to render on screen than bitmap fonts, as they require additional computer code to render the outline to a bitmap for display on screen or in print. Although all types are still in use, most fonts seen and used on computers are outline fonts.
Fonts are designed and created using font editors. Fonts specifically designed for the computer screen and not printing are known as screen fonts.
