Technique used in climbing
Self-rescue (or self-extraction) is a group of techniques in climbing and mountaineering where the climber(s) – sometimes having just been severely injured – use their equipment to retreat from dangerous or difficult situations on a given climbing route without calling on third party search and rescue (SAR) or mountain rescue services for help.
The reasons for a retreat can include an injured or fatigued climber(s) who can no longer continue the climb, the climber(s) having lost their way on the climbing route, a sudden severe storm/bad weather, lost/damaged climbing equipment—or food/water provisions— due to an avalanche or a dropped haul bag, or the route grade is too difficult.
Self-rescue techniques can materially speed up the time taken to get injured climber(s) to safety thus saving lives, and it will also save the climber(s) from being charged for SAR services (e.g. full helicopter rescue is expensive), and avoids putting the SAR team members into harm's way and diverting SAR resources from being able to support other emergencies. In remote locations, there may be no readily available SAR services (e.g. Himalayan climbing on remote peaks), and self-rescue is the only option for the climber(s) to be rescued within a reasonable period that will make treatment viable. 
Not all climbers are familiar with—or skilled in—self-rescue techniques, which can involve carrying out unfamiliar actions with improvised climbing knots in lieu of the correct equipment (e.g. having to safely transfer the loaded tension from a climbing rope to another anchor point, having to complete extended or weight-laden abseils without the correct abseiling device, having to ascend back up a fixed rope without an ascender device, or having to extract a fallen climber from a crevasse without a pulley system), and under difficult circumstances (e.g. with broken limb(s), or in a storm). Self-rescue can be particularly complicated on multi-pitch or big wall climbing routes, and on alpine climbing routes, where the climber(s) are almost continuously hanging from ropes on exposed vertical rock/mountain faces, and very often—particularly for alpine climbing—in bad weather.
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