Typeface - Highway Gothic

One of the most challenging aspects of any design or documentation project is choosing the typefaces. The goals of the project and the target audience must be kept in mind to ensure that the chosen typeface nicely complements the design. For example, the monospace courier typeface, which was designed to simulate the output from a typewriter and is perfect for sample code in an API document, would probably not be an ideal choice for formal invitations. The spacing is too bulky.

Brand-savvy companies often allocate large sums of money to ensure that logos and marketing collateral use a typeface that promotes the company's vision. Technology companies often rely on sleek, futuristic typefaces while traditional companies (e.g. financial and newspaper companies) often rely on exquisite flowing typefaces.

The Federal Transportation Authority, which also spends a considerable amount of money on typeface, must account for more than aesthetic concerns. Safety and readability are primary concerns for transportation officials. This is especially true for the typeface that adorns most of the signs along the United States Interstate Highway System, Highway Gothic. Highway Gothic is a sans serif typeface that was designed for optimal legibility at long distances and great speeds.

This post examines the legibility, readability and "personality" of the Highway Gothic Series E-Modified typeface, which has been used on U.S. Interstate signs for 50+ years. An example of the typeface appears below:



Legibility

A good rule of thumb for determining the legibility of a typeface is to cover the top or bottom half of a word or sentence. If the word or sentence can be easily read by just looking at half of the letters, then the typeface is likely to be perceived as legible. Highway Gothic passes this legibility test. The substantial x-height (height of a typeface's lowercase x) of Highway Gothic coupled with its symmetrical, sharp lines for "straight-line letters" (A,E,F,H,I,K,L,M,N,T,V,W,X,Y,Z) ensure that all letters are easily recognized.

Readability

Readability refers to how easily a line of text can be read. Because Highway Gothic is proportional instead of monospace, the natural appearance and flow of the typeface results in high readability scores. The space between letters ensures that words can be read at great distances. The space within letters, especially the round portions of the "curved-line letters" (B,C,D,G,J,O,P,Q,R,S,U), is generous enough to avoid a sense of constriction or tightness. Also, the generous height of the ascender, which is the distance that letters extend beyond the x-height, has a positive impact on readability.

Personality

Obviously the U.S. Federal Transportation Authority does not randomly select the typeface for road signs of the interstate highway system. For safety purposes, readability in difficult situations (night time driving, fog, rain etc.) was incredibly important. Multiple typefaces were tested, but Highway Gothic was the best fit (although Clearview is slowly replacing Highway Gothic on road signs throughout the U.S Interstate system).

I think the personality of Highway Gothic is conducive to the goals of the U.S. Interstate road signs. The primary goal of the typeface is to relate information (e.g. looking for Trenton? Use exit 42 in ¼ mile), not to appeal to the aesthetics of the reader. I think the clear lines of Highway Gothic emphasize its practical nature. The typeface is straightforward and utilitarian (or workmanlike, if you prefer), not flowing and pretentious.