All fonts are not created equal. When choosing a font for your Web site, make sure to opt for those that are available on your customers' computers and browsers. Otherwise their systems might use a default typeface that's not optimized for online viewing and the site will not appear as you intended.
Since you can't know what system each viewer has, you should create a flexible design and still maintain some control over your Web pages' appearance. Always supply a list of font alternatives, in order of preference.
The two most common font families are serif and sans serif. Serif fonts have cross-lines at the tips of each letter or other embellishments, and fine variations. Sans serif fonts are plain and don't have the decorative embellishments. They vary between thick and thin strokes, compared to fonts from the serif family. Because serifs rely on fine detail, they work well for the high-quality typography of books and magazines. In fact, readability studies have found that most people read serif text faster than sans serif text in print. Sadly, computer screens don't offer the typographical quality of print, so the fine details in the serifs end up not looking so fine after all. As a result, studies of onscreen reading find that sans serif text is the fastest to read, exactly the opposite of the finding for print.
This table outlines the fonts that come preinstalled on most browsers. It's wise not to stray from this list.
Common Fonts and Their Families
When in Doubt, Use Verdana
Even with current technology, screen resolution is much lower than print resolution. Fonts that are ornate or detailed might look fine in print but don't render clearly on the screen, resulting in jagged and degraded text formations.
Using typefaces that are not intended for online reading can be detrimental to your Web site, especially at smaller sizes. Typefaces that are optimized for online viewing tend to be unadorned and crisp, making them easier to read on screens. This table describes the characteristics of the most common fonts.
Characteristics of Common Fonts
Both the serif and sans-serif families have a font that is designed for online reading: Georgia and Verdana, respectively. In general, sans-serif fonts appear more modern than serifs and are more legible at very small sizes. If you're not sure which to use, it's safer to go with Verdana. This sans-serif font is common on all computer systems, works especially well at smaller sizes, and is most pleasant to read on screens. If you're inclined to use a serif typface, Georgia is a good alternative because it also works well for online viewing, although many people prefer Verdanaespecially younger users, who seem to feel that Georgia doesn't match their sense of style. But remember that serif fonts are slightly worse than sans serifs for on-screen reading, so only use Georgia (or other serif typefaces) if your style or banding absolutely requires it.