Web-safe fonts are fonts likely to be present on a wide range of computer systems, and used by Web content authors to increase the likelihood that content displays in their chosen font. If a visitor to a Web site does not have the specified font, their browser tries to select a similar alternative.
To give Web designers some control over the appearance of fonts on their Web pages, even when the specified fonts are not available, the CSS specification allows the use of several generic font families. These families are designed to split fonts into several categories based on their general appearance.
How To Install
The CSS specification allows for multiple fonts to be listed as fallback fonts. In CSS, the font-family property accepts a list of comma-separated font faces to use, like so:
font-family: Helvetica, "Nimbus Sans L", "Liberation Sans", Arial, sans-serif;