In 1906, a small uni­ver­si­ty press in Chica­go pub­lished its stan­dard­ized typo­graph­i­cal prac­tices. Over a hun­dred years lat­er, the Chica­go Man­u­al of Style (CMOS ) is one of the most wide­ly used and respect­ed style guides in the Unit­ed States. The dif­fer­ences between the 1st and 16th edi­tions of Chica­go tell us a sto­ry of how typog­ra­phy has changed over time in the Unit­ed States.

The 1st edi­tion, called sim­ply the Man­u­al of Style, links us to an ear­li­er era. Hand­writ­ten man­u­scripts were still com­mon­place. The type­writer had not yet tak­en the place of promi­nence it would see in years ahead. The 80-page ref­er­ence sec­tion on “Spec­i­mens of Types in Use” fea­tured only the pro­por­tion­al type used in pro­fes­sion­al print­ing for hun­dreds of years. Mono­spaced type­writer type­faces would not appear until lat­er edi­tions.

The 203 pages of the 1st edi­tion con­tained many time­less con­ven­tions. A chap­ter on “Tech­ni­cal Terms” cov­ered typo­graph­ic prin­ci­ples that are still wide­ly held, includ­ing the use of lead­ing, and spac­ing between let­ters and words. But some vari­a­tion from mod­ern use is evi­dent. For exam­ple, the 1906 edi­tion fea­tured semi­colons with­in clos­ing quo­ta­tion marks, and pre­scribed em spaces between sen­tences and after colons.

Dur­ing the next 100 years, the Man­u­al of Style fol­lowed the chang­ing prac­tices of the Eng­lish lan­guage. Allowances were made for the mechan­i­cal lim­i­ta­tions of the typewriter—especially in man­u­scripts. The com­put­er and the advent of dig­i­tal media lat­er caused anoth­er reeval­u­a­tion of typo­graph­ic prin­ci­ples. Final­ly, the chap­ter on “Tech­ni­cal Terms” even­tu­al­ly mor­phed into a chap­ter called “Design and Typog­ra­phy,” seen, for exam­ple, in the 1982 Thir­teenth Edi­tion. But this con­sol­i­da­tion of typo­graph­ic prin­ci­ples with­in the man­u­al was not to last into the 21st cen­tu­ry.

The 16th edi­tion of the CMOS, pub­lished in late 2010, is a much more com­pre­hen­sive work. Music, for­eign lan­guages, and com­put­er top­ics (such as Uni­code char­ac­ters and URLs) have found their way into the style guide. Famil­iar chap­ters have been expand­ed to clar­i­fy ques­tions raised by users. The man­u­al now pro­vides advice on the ital­i­ciza­tion of punc­tu­a­tion, the use of typo­graph­ic quo­ta­tion marks, and mod­ern spac­ing con­ven­tions after ter­mi­nal punc­tu­a­tion, colons and semi­colons. The care­ful read­er will also notice that semi­colons now appear out­side of clos­ing quo­ta­tion marks, along­side its close relative—the colon.

Anoth­er change is evi­dent. The chap­ter on “Design and Typog­ra­phy” is gone. The staff of the Uni­ver­si­ty of Chica­go Press chose to cov­er typo­graph­ic con­ven­tions through­out the man­u­al instead of lump­ing them togeth­er in one chap­ter. Giv­en the diver­si­ty of the mate­r­i­al in the 1026-page 16th edi­tion, that’s an under­stand­able choice. But even though it no longer has a ded­i­cat­ed chap­ter, typo­graph­ic guid­ance is every­where. A cen­tu­ry of change has not dimin­ished its impor­tance in the Chica­go Man­u­al of Style.

And who knows? Per­haps in anoth­er hun­dred years the semi­colon will find its way back inside the clos­ing quo­ta­tion marks.