The ubiquitous Interstate typeface is a relatively new font, 1990s vintage. It is a clean, san serif type with a wide spacing between letters and unique angle-cut ascending and descending strokes. I think what makes it so popular – think Southwest Airlines, Citibank, The Weather Channel and Army Strong (just to name a few) – is that the face works well in large formats and as body text or online. Whatever the reason, chances are you’ve seen it used before.

History of Interstate
Interstate is a digital typeface closely related to the signage alphabet drawn for the U.S. Federal Highway Administration in 1949. It was designed by Tobias Frere-Jones from 1993-1999.