meaning of position: fixed; in html code example

Example 1: css position

h2.pos_left {
  position: relative;
  left: -20px;
}

h2.pos_right {
  position: relative;
  left: 20px;
}

Example 2: popsition relative css

An element with position: relative; is positioned relative to its normal position. Setting the top, right, bottom, and left properties of a relatively-positioned element will cause it to be adjusted away from its normal position. Other content will not be adjusted to fit into any gap left by the element.