Since the era of metal type printing, a font referred to a set of lead pieces for a specific typeface, in a particular style and size. For example, Times New Roman 10 pts, Times New Roman Bold 16 pts, and Times New Roman Bold Italic 16 pts were three distinct fonts of the Times New Roman typeface.

The word font comes from the French fondre, meaning to melt, as characters were cast by pouring molten lead into moulds called matrices.

In the digital era, a font is an independent file containing a typeface in one or more style. In static fonts, one file corresponds to one style. In variable fonts, a single file can include multiple styles through interpolation.
For example:
• Helvetica Neue Light (HelveticaNeue-Light.otf) and Helvetica Neue Light Italic (HelveticaNeue-LightItalic.otf) are two separate static fonts;
• Helvetica VAR (HelveticaVAR.ttf) and Helvetica VAR Italic (HelveticaVAR-Italic.ttf) are variable fonts, each containing a range of styles (Light, Regular, Bold, etc.).