Web Design & Development Guide
Web safe fonts are the fonts guaranteed to be present on all or
most computer systems, and hence can be relied on to display
consistently on webpages. Typically, not having a particular font
installed will cause reversion to some system default font, or, in the
case of alternate character encodings, "garbage" or meaningless
characters to be displayed.
CSS Generic Font Families
The most safe option is to use the generic font families as defined by the
CSS. These are: sans-serif, serif, monospace,
cursive and fantasy. One of them should always be specified as a last
resort for every font-family CSS property.
Microsoft's Core Fonts for the Web
Microsoft has started a Core fonts for the Web initiative. However, despite
the name, only some of the fonts defined there are web-safe indeed. These are:
Arial, Courier New, Times New Roman, Verdana, Trebuchet MS (more recently) and
Lucida Sans (to some extent).
Web-Safe Unicode Fonts
Only two fonts available by default on the Windows platform, Arial and Lucida
Sans, provide a wide Unicode character repertoire. A bug in Verdana (and the
different handling of it by various user agents) hinders its usability where
combining characters are desired.
No dingbats font, including Webdings, can be considered web-safe.
Cascading Style Sheets
Fahrner Image Replacement
Techniques for creating a User Centered Design