Abseiling also known as rappelling is a controlled descent off a vertical drop such as a rock face or top of a rock (as shown in this picture) using a rope. it is also known as rappelling. The word abseiling is from the German 'abseilen' meaning 'to rope down' while rappelling is from the French word 'rappeler' meaning 'to recall or to pull through'.

In the United States, the term rappelling is used nearly exclusively. In the United Kingdom, both terms are understood, but abseiling is strongly preferred. In Australia, New Zealand and Canada, the two terms are used interchangeable. Globally, the term rappelling appears in books written in English more often than abseiling.

This is the technique or method by which people will descend from the top. Climbers, mountaineers, cavers, canyoners, search and rescue and rope access technicians use this technique to descend from cliffs and slopes when they are too steep and/or too dangerous to descend without protection.

To rappel when descending safely, climbers use a variety of techniques to increase the friction on the rope to the point where it can be comfortably controlled. These techniques range from wrapping the rope around their body to using a custom built device called a rack. Climbers choose a technique based on speed, safety, weight and other circumstantial concerns.

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