An ascender is a device used for directly ascending, or for facilitating protection, with a fixed rope when climbing on steep mountain terrain. A form introduced in the 1950s became so popular it begat the term "Jumar" for the device, and the verb "to jumar" to describe its use in ascending.
A pair of left and right handed ascenders (the left rigged to a rope)
Ascenders in use on a single rope on a steep mountain slope, offering the two climbers both security plus an additional aid to their upward ascent. Note that they are not roped together, but are climbing independently of one another.
Aid climbing is a form of rock climbing that uses mechanical devices and equipment, such as aiders, for upward momentum. Aid climbing is different than free climbing, which only uses mechanical equipment for protection, but not to assist in upward momentum. "Aid climbing" sometimes involves hammering in pitons and bolts, into which aiders are clipped, but there is also "clean aid climbing" which avoids hammering, using only removable placements.
Climber standing in aiders while ascending aid climbing route, The Shield (VI 5.7 A3), on El Capitan
Royal Robbins resting on his aiders during the 3rd pitch of the FA of the Salathé Wall (VI 5.9 C2)
Daisy chain
Piton
