Besides color, typography is a designer's most creative and effective tool. Typography has personal voice and personality. Used competently, type communicates information easily, and conveys conceptual themes artistically.
Your written text needs a visual hierarchy which encourages your reader to scan the page and find the information they seek. Good visual design organizes written content from most important to least important, by assigning large, medium, and small type heading styles, usually with the same typeface, yet varying size and weight.
Headlines tend to be sized 24 points or more and require spacing adjustment, referred to as kerning. Body copy size ranges from 9 to 12 points. When a line of type is adjusted for spacing, designers refer to this as tracking.
Typography can be categorized as serif or sans serif typefaces. Serif fonts contain decorative flare marks at the end or beginning of some letters. Sans serif fonts are plain and without embellishment. Serif typefaces are generally chosen for large amounts of text with sans serif frequently selected for headings. Two fonts specifically designed for legibility on the web are Georgia (serif) and Verdana (sans serif.)
Typographic styles vary considerably. Familiarity with their diverse personalities helps guide decisions about which typefaces are most legible to convey your identity and theme. As a rule of thumb, decorative fonts are best used sparingly, if at all, due to legibility and unity considerations in a composition.
Other guidelines to use type competently include: