Breaking down the different types of letterforms.
Old Style
• The axis of thick/thin slopes slightly left
• Greater contrast between thick and thin
• Cross bar of the "e" is horizontal
• Top serifs are roof-shaped and triangular
• Base serifs have hardly any or no rounding
As evidenced in Bembo, Plantin, Garamond Sabon, Albertina
Transitional
• Axis of transition is vertical or slopes slightly left
• Base serif is slightly rounded
• Lowercase "e" crossbar is horizontal
• Top serifs of lowercase letters are roof-shaped
• ROunded, sharpened, or horizontal serifs
Qualities shown in Baskerville, Concorde, Fournier, Perpetua, Caslon, Old Face, Times New Roman
Modern
• Emphasis on vertical stroke and sharp contrasts
• Symmetry and sharp transition to straight
• Axis is vertical
• Easy adjustments to thickness and width allow for many variants
Examples are Filla Sophia, Bodoni, Didot, Walbaum, Linotype, Centennial
Slab
• Little contrast between thick and thin
• Heavy rectangular serifs – thick as the letters themselves
• SUbdivided by lowercase letters
• Appear to be sans serif with serifs added
Can be seen in Memphis, Antique, First Clarendon, Beton, PMN Caecilia, Serifa
Grotesk
• Angular letterforms
• Calligraphic shape and movement
• Very distinct in appearance
• Old fashioned looking, formal
Grotesk typefaces include Cloister Clack, Alte Schwabacher, San Marco, Luthersche Fraktur, Fette Fraktur
Geometric
• No serifs
• Thickness only minimally and visually connected
• Vertical axis
• Very precise lettering
As seen in Futura, Avant Garde, Eurostile, Erbar, Neuzeit Grotesk