Font is used synonymously with the term typeface and has it origin since the beginning of 1980's.
Different sizes of a single style—separate fonts in metal type—are now generated from a single computer font, because vector shapes can be scaled freely.
Several characteristics which may distinguish fonts, though they would also depend on the script(s) that the typeface supports. In European alphabetic scripts, i.e. Latin, Cyrillic and Greek, the main such properties are the stroke width, called weight, the style or angle and the character width.
Beginning in the 1980s, with the introduction of computer fonts, a broader definition for the term "font" evolved. Different sizes of a single style—separate fonts in metal type—are now generated from a single computer font, because vector shapes can be scaled freely. "Bulmer", the typeface, may include the fonts "Bulmer roman
The term font, a doublet of the word fondue, derives from Middle French font, meaning "(something that has been) melt(ed)", referring to type produced by casting molten metal
The weight of a particular font is the thickness of the character outlines relative to their height. A typeface may come in fonts of many weights, from ultra-light to extra-bold or black; four to six weights are not unusual, and a few typefaces have as many as a dozen