The font stack
font-family

Specify the "font stack" for the element, informing the browser which fonts are preferred and which are acceptable replacements.
Property values
Provide the names of one or more fonts that are acceptable equivalents. The first one that is present on the user's device will be used.
Surround the name with quotation marks if it contains spaces, like "Times New Roman". Separate each name in the stack with commas.
The last font name in the the stack should be one of these generic names:
serif | These fonts have flared or tapered ends |
sans-serif | These fonts do not have flared or tapered ends |
monospace | Each character in these fonts occupies the same horizontal width |
cursive | These fonts have connecting strokes which make adjacent charcters appear to run together |
fantasy | Highly decorative fonts that stretch the typical form of each character into fantastic shapes |
system-ui | This is the user's device-specific standard font for its user-interface |
emoji | Special fonts that contain emojis rather than characters |
math | Fonts that have support for brackets, expressions, superscripts, subscripts and other mathematical concerns |
fangsong | A Chinese government style font |
Examples
font-family: 'Source Serif Pro', serif;