font-family

Defines the font for an element, either as a specific font or as one of the generic fonts serif, sans-serif, monospace, cursive, and fantasy.

Usage:

style="font-family: Times,'Times New Roman',serif;"

NOTES:
Does not work in GMail.
The cursive and fantasy generic font types do not work consistently when used in e-mail.

Workaround:
Define fonts like this:
<font face="Times,'Times New Roman',serif" size="2" style="font: 10pt Times,'Times New Roman',serif;">

The shorthand value for font-family is supported on all e-mail clients.