how to name variables in sass code example

Example 1: SCSS variables

$font-stack:    Helvetica, sans-serif;
$primary-color: #333;

body {
  font: 100% $font-stack;
  color: $primary-color;
}

Example 2: variables scss

// SCSS variables

$darkcolor: #605C4D;
$large: 350px;

section{
	background-color: $darkcolor;
  	height: $large;
}