A bear bag is a method of hanging food and scented items in a bag from a tree branch, out of a bear's reach, to protect it overnight. Techniques like the PCT method suspend the bag high and away from the trunk. Bear bags are lighter than canisters but harder to do well, and are banned where canisters are required.
A bear canister is a hard-sided, bear-resistant container that backpackers use to store food, trash, and scented items overnight, keeping them from bears. Required in many wilderness areas, canisters protect both hikers and bears — a bear that gets human food often becomes dangerous and may have to be killed.
Gaiters are protective sleeves worn over the lower leg and the top of the boot to keep out snow, mud, scree, water, and debris. They range from low trail gaiters that block trail grit to tall, waterproof mountaineering gaiters for deep snow, and keep feet drier and more comfortable on rough terrain.
Trekking poles are adjustable, lightweight poles used in pairs to improve balance, reduce strain on the knees and legs, and add power on climbs and descents. They help on steep, uneven, or slippery terrain and when crossing streams, and are a popular aid for hikers and backpackers of all levels.
A neutral climbing shoe has a flat, relaxed shape that keeps the foot comfortable and supports all-day climbing, crack climbing, and beginners. It sacrifices some power on steep terrain compared with downturned aggressive shoes, but its comfort and versatility make it the usual choice for a first pair.
An aggressive climbing shoe has a strongly downturned (cambered) shape and an asymmetric toe that concentrate power onto the big toe, making it excel on steep, overhanging rock and small holds. The trade-off is comfort: aggressive shoes are tight and not designed for long days or beginners.
An auto belay is an automated belay device installed at the top of a climbing-gym wall that takes in slack as you climb and lowers you smoothly if you let go or fall. It lets climbers practice roped climbing alone, without a human belayer — though clipping in correctly every single time is essential.
A figure-eight device is a metal '8'-shaped descender used mainly for rappelling, where the rope threads through the large ring to create friction. Once common for belaying too, it is now largely a rappel and rescue tool, valued for dissipating heat on long descents but prone to twisting the rope.
A plaquette is a tube-style belay device with extra slots that allow 'guide mode' — belaying one or two following climbers directly off the anchor, with the device automatically locking if a follower falls. This makes plaquettes the standard choice for multi-pitch climbing, where they free the leader's hands at the belay.
An assisted-braking device (ABD) is a belay device with a mechanism — usually a camming lever — that helps pinch and lock the rope when it's loaded suddenly, adding a margin of safety in a fall. The GriGri is the best-known example. Crucially, ABDs still require a hand on the brake at all times; they are not hands-free.