The Prussik Knot
The Prusik knot is the best known of a family of knots that are used to attach a moving "clamp" to another rope. This clamp may be used to either ascend the rope or provide a form of backup when abseiling. Easy to form, it has been superceded in recent years by its more advanced cousins.
| Attribute | Notes |
| Strength | |
| Ease of Tying | Very easy to tie. |
| Recognisable | Very good in this respect. |
| Also known as | None known. |
| Usage | Security whilst abseiling. Ascending ropes. The Prusik (and its variations) are the only method that permits the ascending of double or twin ropes, all mechanical devices work on single ropes. |
| Advantages | Simple, easily understood. |
| Disadvantages | Can jam under load. Cannot be moved whilst under load. |