Pattern heddles, used in combination with long-eye heddles, are the essence of weaving on the drawloom. These two kinds of heddles used together allow you to create two sheds: a "pattern shed" with the pattern heddles, and a "ground shed" with the long-eye heddles.
The pattern heddles need to be long, because they make a very large shed at the back of the loom, which is often outfitted with a loom extension. Sometimes lingos (weights) are used at the bottom of each pattern heddle, or a group of pattern heddles, or sometimes a weighted lower shaft bar is used.
If you'd like to learn more about drawloom weaving, Becky's DVD Dress Your Swedish Drawloom contains the most comprehensive instructions to be found. Or, even better: come take one of our Drawloom classes!