How are carabiners used in rock climbing?

In rock climbing, a carabiner—often referred to as a snap link—is a metal ring featuring a spring-hinged side used primarily as a safety component.12

Carabiners are utilized in the following ways:

• Safety and Protection: They are snapped into anchors (such as chocks, pitons, bolts, or "friends") to create a system through which the climbing rope can be passed. This setup is designed to provide maximum safety by securing the rope while minimizing effort during ascent and descent.2
• Tension Climbing: In this specific technique, a leader is supported by a series of anchors and carabiners. The rope is passed through these points, allowing the climber to be supported by their partners while they move upward to place the next anchor.2
• Snow and Ice Climbing: On difficult terrain, carabiners are used in conjunction with ice pitons, which are driven into the surface and allowed to freeze in place to provide secure attachment points.2

Proper placement of these devices is essential to ensure the rope remains free from hazards like sharp edges or cracks where it could become jammed or damaged.2