Stationary Rope Systems (SRS) have long been used in caving, mountaineering and tree canopy access. SRS has become a big part of many tree climbers' strategies for ascent. Recent gear innovations have provided methods to not only ascend but also perform tree work on SRS.
SRS is fundamentally different than Moving Rope System (MRS, sometimes called DdRT or Doubled Rope Technique). In SRS, the climber moves along the line, and the rope is anchored and does not move in the system. The mechanical advantage gained through a doubled rope is removed, but the rate of ascent on the rope becomes a 1:1 ratio and with a rope walker setup, can be extremely fast. SRS climbing is frequently used for long ascents, or to more easily install a line as there is no need to isolate the primary suspension point.