This SVG example demonstrates how to create open and closed linear paths.

ClosedAndOpenLinearPaths.svg

<svg width="225" height="150" xmlns="http://www.w3.org/2000/svg" version="1.1">
  <path d="M 25,25 L100,25 L100,100 Z 
           M 125,25 L200,25 L200,100" fill="none" stroke="black" />
</svg>

Output