Font or Typeface?
Confused by the terms? That’s probably because it’s confusing!
But here’s the simple way to think of it.
Typeface: is the design of the alphabet--the shape of the letters that make up the typestyle. The letters, numbers, and symbols that make up a design of type. So when you say “Arial” or “Goudy” you’re talking about a set of letters in a specific style.
Font: is the digital file that contains/describes the typeface. Think of the font as a little piece of software that tells the computer and printer how to display and print the typeface.
According to Adobe’s type gloassary: “A font is one weight, width, and style of a typeface. Before scalable type, there was little distinction between the terms font, face, and family. Font and face still tend to be used interchangeably, although the term face is usually more correct.”
If you want to get a little deeper:
A typeface family is a group of typefaces that were designed to be used together. For example, Goudy Old Style has Roman (upright or normal), italic (slanted and cursive), bold and bold italic versions. Each of the style and weight combinations is called a face or typeface, and together they are, hopefully, a happy typeface family (rather than a disfunctional typeface family which will probably be more familiar to you).
For more typographic terms, see Adobe’s Type Glossary