The terms "typeface" and "font" are often used interchangeably. In fact, when most people say "font," what they're really referring to is a typeface. As a graphic designer, it's important to understand the difference between these terms in order to avoid any kind of misunderstanding or to just look more professional at typography. 

A typeface is a family of fonts. Some familiar examples include Times New Roman, Arial, and Brush Script. A font is a variation of a typeface, typically bold, italic, or a combination of the two.

Examples of fonts include Times New Roman Italic and Arial Bold.

Proxima Nova is a flexible typeface that encompasses many different fonts. 

People keep using these terms interchangeably because most designers are used to working on, where you install fonts and then select them from the Font menu, we tend to use the word font in daily discourse, but if you are asked by an executive creative director what font you’ve used in a project, it’s possible they want to know the precise details. 

Helvetica would be the typeface chosen for the project like designing wedding invitation card, but the font might be Helvetica Regular 9 point.