Stem

The primary vertical (or near-vertical)
Stroke
of a letterform, serving as the structural backbone of characters such as l, d, b, h, and the uprights of H, M, and N. Stem
Weight
is the main determinant of a
Typeface
apparent boldness and, together with the thinnest strokes, defines the stroke contrast ratio that distinguishes subgroups like
Old Style Serif
,
Transitional Serif
, and
Modern Serif
serifs.