Climbers have different purposes:for binding ropes (including different thicknesses), for fixing climbing straps, for stationary fastening of ropes, as a device for lowering / lifting for lack of other means, and so on.
Bowline
Serves mainly to fix the strapping.The end of the rope is passed through all the straps of the strap (upper and lower), then knot is knit. It can also be used to create an impromptu harness from the end of the rope in an emergency situation: the free end wraps around the chest and the bugles are tied (similarly, tourist watermakers act when you need to urgently pull a person out of the river). To fix the strapping in some cases, other climbing nodes can be used, for example, a straight line with control knots. The beeline serves also for fastening the peristal rope with a loop around the stone or wood without the use of a carbine.
Eight
It is a more reliable analogue of the node-conductor.The same conductor, only with an additional turn. With the help of a figure eight and a carbine, the climber is fastened to the safety rope; stationary railings are attached to the hook or icebreaker by a figure eight through a rifle.
To bind ropes of equal thickness (for example,when there is a need to build a rope) use mountaineering knots straight and grapevine. The latter is more reliable (the direct node must be fixed with control knots), but it has a significant drawback: when tightened, it is almost impossible to untie it. In some cases, you can build a rope by connecting two conductors with a carbine.
Prusik (grasping knot)
Designed for lifting / lowering on fixedrailings. The classic way. Now for these purposes another climbing equipment is used: for lifting - jumars, for descent - eight, petals, etc. It is more convenient than a knot. Prusik is also used as a clamp of a stretched rope when working with a pulley (a system by which a group pulls a victim out of a crack, pulls a hard crossing over a river, etc.).
"Hare ears"
Used for insurance, which requires increased reliability. For example, for lifting an incompetent participant from the crack with an attendant.
There are climbing knots for binding ropes having different thicknesses, the main rope and a ribbon: counter, brumchkotovy. In real life, infrequently.
Stirrup
Used, for example, when climbingfixed rope. The loop with the stirrup for the leg is attached to the Jumar, the second Zhumar is fastened to the chest strapping. Zhumar with a loop extends up the rope, the climber rises on the stirrup and moves the chest Zhumar to the foot. Stirrups are used to lift the victim, if he is able to move himself, and in some other cases.
All these nodes are mountaineering, but some of themwas invented before, then they were considered marine. And now they are used not only in mountaineering or industrial alpinism, but also in other types of extreme activities: water and speleotourism, rescue operations and any situations where a safety rope is required.
