Here, we discuss some typography basics. While this information is not essential, many font lovers will find it interesting.
Typically, typefaces come in groups of a few variants. For example, most fonts come with a bold, italic, and bold-italic variant. Some fonts may also have small caps, and demibold variants. A group of fonts consisting of a font and its variants is called a family of typefaces. For example, the Garamond family consists of Garamond, Garamond-italic, Garamond-bold, Garamond bold-italic, Garamond demi-bold, and Garamond demi-bold-italic. The Adobe expert Garamond font also makes available Garamond small caps, and Garamond titling capitals.
There are several classifications of typefaces. Firstly, there are fixed width fonts, and variable width fonts. The fixed width fonts look like typewriter text, because each character is the same width. This quality is desirable for something like a text editor or a computer console, but not desirable for the body text of a long document. The other class is variable width. Most of the fonts you will use are variable width, though fixed width can be useful also (for example, all the example shell commands in this document are illustrated with a fixed width font). The most well known fixed width font is Courier.
Serifs are little hooks on the ends of characters. For example, the letter i in a font such as Times Roman has serifs protruding from the base of the i and the head of the i. Serif fonts are usually considered more readable than fonts without serifs. There are many different types of serif fonts.
Sans serif fonts do not have these little hooks, so they have a starker appearance. One usually does not write a long book using a sans serif font for the body text. There are sans serif fonts that are readable enough to be well suited to documents that are supposed to be browsed / skimmed (web pages, catalogues, marketing brochures). Another application that sans serif fonts have is as display fonts on computer screens, especially at small sizes. The lack of detail in the font can provide it with more clarity. For example, Microsoft touts Verdana as being readable at very small sizes on screen.
Notable sans serif fonts include Lucida Sans, MS Comic Sans, Verdana, Myriad, Avant Garde, Arial, Century Gothic and Helvetica. By the way, Helvetica is considered harmful by typographers. It is somewhat overused, and many books by typographers plead users to stay away from it.
Old style fonts are based on very traditional styles dating as far back as the late 15th century. Old style fonts tend to be conservative in design, and very readable. They are well suited to writing long documents. The name ``old style'' refers to the style of the font, as opposed to the date of its design. There are classic old style fonts, such as Goudy Old Style, which were designed in the 20th century. The old style class of fonts has the following distinguishing features:
Well defined, shapely serifs.
Diagonal emphasis. Imagine drawing a font with a fountain pen, where lines 45 degrees anticlockwise from vertical are heavy and lines 45 degrees clockwise from vertical are light. Old style fonts often have this appearance.
Readability. Old style fonts are almost always very readable.
Subtlety and lack of contrast. The old style fonts have heavy lines and light lines but the contrast in weight is subtle, not stark.
Notable Old Style fonts include Garamond, Goudy Old Style, Jenson, and Caslon (the latter is contentious -- some consider it transitional)
The moderns are the opposite of old style fonts. These fonts typically have more character, and more attitude than their old style counterparts, and can be used to add character to a document rather than to typeset a long piece. However, nothing is black and white -- and there are some modern fonts such as computer modern and Monotype modern, and New Century Schoolbook which are very readable (the contrast between heavy and light is softened to add readability). They are based on the designs popular in the 19th century and later. Their distinguishing features include:
Lighter serifs, often just thin horizontal lines.
Vertical emphasis. Vertical lines are heavy, horizontal lines are light.
Many moderns have a stark contrast between light and heavy strokes.
Modern typefaces with high contrast between light and heavy strokes are not as readable as the old style fonts.
Bodoni is the most notable modern. Other moderns include computer modern, and Monotype modern (on which computer modern is based).
Transitional fonts fit somewhere in between moderns and old style fonts. Many of the transitional's have the same kind of readability as the old styles. However, they are based on slightly later design. While a move in the direction of the moderns may be visible in these fonts, they are still much more subtle than the moderns. Examples of transitional's include Times Roman, Utopia, Bulmer, and Baskerville. Of these, Times leans towards old style, while Bulmer looks very modern.
The slab serif fonts are so named because they have thick, block like serifs, as opposed to the smooth hooks of the old styles or the thin lines of some of the moderns. Slab serif fonts tend to be sturdy looking and are generally quite readable. Many of the slab serifs have Egyptian names -- such as Nile, and Egyptienne (though they are not really in any way Egyptian). These fonts are great for producing readable text that may suffer some dilution in quality (such as photocopied documents, and documents printed on newspaper). These fonts tend to look fairly sturdy. The most notable slab serif fonts are Clarendon, Memphis and Egyptienne, as well as several typewriter fonts. Many of the slab serif fonts are fixed width. Conversely, most (almost all) fixed width fonts are slab serif.
Surprisingly, the rise of sans serif fonts is a fairly recent phenomenon. The first well known sans serif fonts were designed in the 19th early 20th century. The earlier designs include Futura, Grotesque and Gill Sans. These fonts represent respectively the ``geometric'', ``grotesque'' and ``humanist'' classes of sans serif fonts.
The grotesques where so named because the public were initially somewhat shocked by their relatively stark design. Groteques are very bare in appearance due to the absence of serifs, and the simpler, cleaner designs. Because of their ``in your face'' appearance, grotesques are good for headlines. The more readable variations also work quite well for comic books, and marketing brochures, where the body text comes in small doses. Grotesques don't look as artsy as their geometric counterparts. Compared to the geometrics, they have more variation in weight, more strokes, they are squarer (because they don't use such circular arcs). They use a different upper case G and lower case a to the geometrics. While they are minimalistic but don't go to the same extreme as the brutally avant-garde geometrics.
Notable grotesques include the overused Helvetica, Grotesque, Arial, Franklin Gothic, and Univers.
The Futura font came with the manifesto: form follows function. The geometric class of fonts has a stark minimalistic appearance. Distinguishing features include a constant line thickness (no weight). This is particularly conspicuous in the bold variants of a font. Bold groteques and humanist fonts often show some notable variation in weight while this rarely happens with the geometric fonts. Also notable is the precise minimalism of these designs. The characters almost always are made up from straight horizontal and vertical lines, and arcs that are very circular (to the point where they often look as though they were drawn with a compass). The characters have a minimal number of strokes. This gives them a contemporary look in that they embrace the minimalistic philosophy that would later take the world of modern art by storm. A tell tale sign that a font is a geometric type is the upper case ``G'', which consists of a minimalistic combination of two strokes -- a long circular arc and a horizontal line. The other character that stands out is the lower case ``a'' -- which is again two simple strokes, a straight vertical line and a circle (the other ``a'' character is more complex which is why it is not used). Notable geometrics include Avant Garde, Futura, and Century Gothic.
As the name might suggest, humanist fonts were designed with a goal of being less mechanical in appearance. In many ways, they are more similar to the serif fonts than the geometrics and the grotesques. They are said to have a ``pen drawn'' look about them. They tend to have subtle variation in weight, especially observable in bold variants. The curve shapes are considerably less rigid than those of the geometrics. Many of them are distinguishable by the ``double story'' lower case g, which is the same shape as the g used in the old style serif fonts. The humanist typefaces are the easiest to use without producing an ugly document as they are relatively compatible with the old style fonts.
Grouping typefaces is not easy, so it pays to avoid using too many on the one page. A logical choice of two typefaces consists of a serif and a sans serif. Monotype's Typography 101 page provides a category-matchup. They conclude that the moderns and geometrics form good pairs, while the old styles and humanists also go together well. The transitionals are also paired with the humanists. The slab serifs are paired with the grotesques, and some variants of the slab serifs are also said to match the geometrics or humanists.
From reading this, one gets the impression that their philosophy is essentially to match the more conservative serifs with the more moderate sans serifs, and pair the wilder modern serifs with the avant garde looking (pun unavoidable) geometrics.
Properly spacing fonts brings with it all sorts of issues. For example, to properly typeset the letters ``fi'', the i should be very close to the f. The problem is that this causes the dot on the i to collide with the f, and the serif on the head of the i to collide with the horizontal stroke of the f. To deal with this problem, font collections include ligatures. For example, the ``fi'' ligature character is a single character that one can substitute for the two character string ``fi''. Most fonts contain fi and fl ligatures. Expert fonts discussed later often include extra ligatures, such as ffl, ffi, and a dotless i character.
Small caps fonts are fonts that have reduced size upper case letters in place of the lower case letters. These are useful for writing headings that require emphasis (and they are often used in LaTeX). Typically, when one writes a heading in small caps, they use a large cap for the beginning of each word, and small capitals for the rest of the word (``title case''). The advantage of this over using all caps is that you get something that is much more readable (using all caps is a big typographic sin).
Font metrics define the spacing between variable width fonts. The metrics include information about the size of the font, and kerning information, which assigns kerning pairs -- pairs of characters that should be given different spacing. For example, the letters ``To'' would usually belong in a kerning pair, because correctly spaced (or kerned), the o should partly sit under the T. Typesetting programs such as LaTeX need to know information about kerning so that they can make decisions about where to break lines and pages. The same applies to WYSIWYG publishing programs.
The other important component of a font is the outline, or shape. The components of the fonts shape (a stroke, an accent, etc) are called glyphs.