The knots belonging to this category are the basic ones required for search and rescue. They are very reliable and safe as they find application in survival situations. Another important property is that they can be untied fairly easily. They are used for firefighting, climbing, high angle, confined space and swift water rescue, rigging, tying rescue harnesses, and other activities connected with rescue operations. Boy scouts are given special training for tying these knots. It is advisable to commit them to memory since you would require them in emergency conditions.