Serif fonts are often recognized as easier to read than sans serif fonts, the term for the kind of font that does not have serifs. Therefore, serif fonts are considered somewhat better than sans serif fonts for body text. A common rule of thumb when selecting typography is to use a sans serif font for the header text and a serif font for the body text.
Old style serif fonts are the oldest type of serif font. Old style serif fonts are characterized by only moderate transitions between the thinner and thicker parts of the stroke with a diagonal stress, meaning that the thinnest parts of strokes on a diagonal. Old style fonts work well for body text. Examples of old style fonts are Garamond, Palatino, Goudy Old Style and Minion.
Serif fonts in the transitional style fall between the old style and the modern style. Transitional serif fonts are characterized by a horizontal stress, unlike the old style which features a diagonal stress, and have a moderately higher contrast between the thinner and thicker parts of strokes than old style fonts. Transitional fonts are quite common and include Times New Roman and Baskerville. They are considered to be a neutral font and work well for body text.
Slab serif fonts are almost like the serif form of the sans serif, in that that strokes are generally of equal weight or have little variation, and the serifs are thick and often angular. Slab serifs tend to be good for body text. Some slab serif fonts are monospace, such as Courier. All the letters and spaces in a monospace font are the same, making them excellent for coding or in any situation in which uniformity is desired. Examples of the slab serif style are Rockwell, Courier and Clarendon.
Modern serif fonts are characterized by a high contrast between the thinnest and thickest parts of strokes and have very thin serifs, often hairline thin. The modern serif font style is not connected to how recent the font was developed. The modern style first appeared in the late 1700s. Of the different serif fonts, it is the most decorative and the least suitable for body text. Common examples are Bodoni and Didot.