Typeface anatomy

Typeface anatomy describes the graphic elements that make up printed letters in a typeface.

The strokes of a letter are the lines that make it up. Strokes may be straight, as in k l v w x z, or curved, as in c o s. If straight, they may be horizontal, vertical, or diagonal; if curved, open or closed. Typographers also speak of an instroke, where one starts writing the letter, as at the top of a c f, and an outstroke, where the pen leaves off, as at the bottom of c e j k t y.

Typefaces are born from the struggle between rules and results. Squeezing a square about 1% helps it look more like a square; to appear the same height as a square, a circle must be measurably taller. The two strokes in an X aren't the same thickness, nor are their parallel edges actually parallel; the vertical stems of a lowercase alphabet are thinner than those of its capitals; the ascender on a d isn't the same length as the descender on a p, and so on. For the rational mind, type design can be a maddening game of drawing things differently in order to make them appear the same.

A main vertical stroke is called a stem. The letter m has three, the left, middle, and right stems. The central stroke of an s is called the spine. A stroke, usually a stem, which rises above the height of an x (called the x height) is called an ascender. Letters with ascenders are b d f h k l. A stroke which drops below the baseline is a descender. Letters with descenders are g j p q y. An arching stroke is called a shoulder or sometimes just an arch, as in h n m. A closed curved stroke is called a bowl in b d o p q D O P Q R; B has two bowls. A trailing outstroke, as in j k y J K Q R is called a tail. A short horizontal stroke, as in the center of e f t A and the middle stroke of E F, is called a bar. A longer horizontal stroke at the top or bottom, as in E F L T, is called an arm. The bottom of the two-story g is called a loop; the very short stroke at the top is called the ear.i j each have a dot, jot, or tittle. Angles of strokes are called apices if at the top and vertices if at the bottom. w has one apex and two vertices; v has one vertex.

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