pseudo-follower collects. When the leader runs low on gear they construct a belay station where the follower can join them to exchange gear. The stronger climber is often the pseudo-follower since a fall by the follower would pull the leader from below towards the last piece of gear—a potentially devastating fall for the leader. In contrast, a fall from the leader would pull the follower from above, resulting in a less serious fall. Most speed ascents involve some form of simul climbing but may also include sections of standard free climbing and the use of placed gear for advancement (i.e. partial aid or pulling on gear). Grading systems Climbing communities in many countries and regions have developed their own rating systems for routes. Ratings, or grades, record and communicate consensus appraisals of difficulty. Systems of ratings are inherently subjective in nature, and variation of difficulty can be seen between two climbs of the same grade. Hence, there may be occasional disagreements arising from physiological or stylistic differences among climbers. The practice of rating a climb below its actual difficulty is known as sandbagging. The most commonly used rating systems in the United States are the Yosemite Decimal System and the Hueco V-scale bouldering grade. The current ranges for climbing routes are 5.0 for easy beginner routes to 5.15 being world class and V0–V16, respectively. As the limit of human climbing ability has not yet been reached, neither grading system has a definite endpoint and they are thus subject to revision. The ratings take into account multiple factors affecting a route, such as the slope of the ascent, the quantity and quality of available handholds, the distance between holds, ease of placing protection and whether advanced technical maneuvers are required. Typically the rating for the hardest move on the wall will be the rating for the whole climb. While the height of a route is generally not considered a factor, a long series of sustained hard moves will often merit a higher grade than a single move of the same technical difficulty. For example, a climb with multiple 5.11 moves with no rests may thus be rated a 5.12. Terminology As climbing routes or problems increase in difficulty, climbers learn to develop skills that help them complete the climbs clean. There are several techniques for hands and feet as well as terms for motions that combine the two. For indoor gyms,