Check out example codes for "sans serif font family css". It will help you in understanding the concepts better.

Code Example 1

<style>
.sansserif {
font-family: Arial, Helvetica, sans-serif;
}
</style>

Code Example 2

font-family: "Times New Roman", Georgia, serif;
/* If the browser does not support the first font (ie: Times New Roman),
it will then try the next font (ie: Georgia). The last font should always
be a "generic-family" font (ie: serif, sans-serif, etc..).
/* If font is more then one word, it must be put into quotes. */

Code Example 3

/* Answer to: "default font family css" */

/*
  The font family of a text is set with the font-family property.

  The font-family property should hold several font names as a
  "fallback" system. If the browser does not support the first font,
  it tries the next font, and so on. 

  Start with the font you want, and end with a generic family, to let
  the browser pick a similar font in the generic family, if no other
  fonts are available.

  For more information, go to:
  https://www.w3schools.com/css/css_font.asp
*/

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