Compass in the context of Brunton compass

Ancient Chinese scientists and engineers made significant scientific innovations, findings and technological advances across various scientific disciplines including the natural sciences, engineering, medicine, military technology, mathematics, geology and astronomy.

Among the earliest inventions were the abacus, the sundial, and the Kongming lantern. The Four Great Inventions – the compass, gunpowder, papermaking, and printing – were among the most important technological advances, only known to Europe by the end of the Middle Ages 1000 years later. The Tang dynasty (AD 618–906) in particular was a time of great innovation. A good deal of exchange occurred between Western and Chinese discoveries up to the Qing dynasty.

The four cardinal directions or cardinal points are the four main compass directions: north (N), east (E), south (S), and west (W). The corresponding azimuths (clockwise horizontal angle from north) are 0°, 90°, 180°, and 270°.

The four ordinal directions or intercardinal directions are northeast (NE), southeast (SE), southwest (SW), and northwest (NW).The corresponding azimuths are 45°, 135°, 225°, and 315°.

China has been the source of many innovations, scientific discoveries and inventions. This includes the Four Great Inventions: papermaking, the compass, gunpowder, and early printing (both woodblock and movable type). The list below contains these and other inventions in ancient and modern China attested by archaeological or historical evidence, including prehistoric inventions of Neolithic and early Bronze Age China.

The historical region now known as China experienced a history involving mechanics, hydraulics and mathematics applied to horology, metallurgy, astronomy, agriculture, engineering, music theory, craftsmanship, naval architecture and warfare. Use of the plow during the Neolithic period Longshan culture (c. 3000 – c. 2000 BC) allowed for high agricultural production yields and rise of Chinese civilization during the Shang dynasty (c. 1600 – c. 1050 BC). Later inventions such as the multiple-tube seed drill and the heavy moldboard iron plow enabled China to sustain a much larger population through improvements in agricultural output.

The Four Great Inventions are inventions from imperial China that are celebrated in Chinese culture for their historical significance and as symbols of ancient China's advanced science and technology. They are the compass, gunpowder, papermaking and printing.

These four inventions had a profound impact on the development of civilization throughout the world. However, some modern Chinese scholars have opined that other Chinese inventions were perhaps more sophisticated and had a greater impact on Chinese civilization – the Four Great Inventions serve merely to highlight the technological interaction between East and West.

During the High Middle Ages, the Islamic world was an important contributor to the global cultural scene, innovating and supplying information and ideas to Europe, via Al-Andalus, Sicily and the Crusader kingdoms in the Levant. These included Latin translations of the Greek Classics and of Arabic texts in astronomy, mathematics, science, and medicine. Translation of Arabic philosophical texts into Latin "led to the transformation of almost all philosophical disciplines in the medieval Latin world", with a particularly strong influence of Muslim philosophers being felt in natural philosophy, psychology and metaphysics. Other contributions included technological and scientific innovations via the Silk Road, including Chinese inventions such as paper, compass and gunpowder.

The Islamic world also influenced other aspects of medieval European culture, partly by innovations made during the Islamic Golden Age, including various fields such as the arts, agriculture, alchemy, music, pottery, etc.

A firestorm is a conflagration which attains such intensity that it creates and sustains its own wind system. It is most commonly a natural phenomenon, created during some of the largest bushfires and wildfires. Although the term has been used to describe certain large fires, the phenomenon's determining characteristic is a fire with its own storm-force winds from every point of the compass towards the storm's center, where the air is heated and then ascends.

The Black Saturday bushfires, the 2021 British Columbia wildfires, and the Great Peshtigo Fire are possible examples of forest fires with some portion of combustion due to a firestorm, as is the Great Hinckley Fire. Firestorms have also occurred in cities, usually due to targeted explosives, such as in the aerial firebombings of London, Hamburg, Dresden, and Tokyo, and the atomic bombing of Hiroshima.

A compass rose or compass star, sometimes called a wind rose or rose of the winds, is a polar diagram displaying the orientation of the cardinal directions (north, east, south, and west) and their intermediate points. It is used on compasses (including magnetic ones), maps (such as compass rose networks), or monuments. It is particularly common in navigation systems, including nautical charts, non-directional beacons (NDB), VHF omnidirectional range (VOR) systems, satellite navigation devices ("GPS").

A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, one that measures the direction of an ambient magnetic field, in this case, the Earth's magnetic field. Other magnetometers measure the magnetic dipole moment of a magnetic material such as a ferromagnet, for example by recording the effect of this magnetic dipole on the induced current in a coil.

The invention of the magnetometer is usually credited to Carl Friedrich Gauss in 1832. Earlier, more primitive instruments were developed by Christopher Hansteen in 1819, and by William Scoresby by 1823.

Magnetic declination (also called magnetic variation) is the angle between magnetic north and true north at a particular location on the Earth's surface. The angle can change over time due to polar wandering.

Magnetic north is the direction that the north end of a magnetized compass needle points, which corresponds to the direction of the Earth's magnetic field lines. True north is the direction along a meridian towards the geographic North Pole.

Gerolamo Cardano (Italian: [dʒeˈrɔːlamo karˈdaːno]; also Girolamo or Geronimo; French: Jérôme Cardan; Latin: Hieronymus Cardanus; 24 September 1501– 21 September 1576) was an Italian polymath whose interests and proficiencies ranged through those of mathematician, physician, biologist, physicist, chemist, astrologer, astronomer, philosopher, music theorist, writer, and gambler. He became one of the most influential mathematicians of the Renaissance and one of the key figures in the foundation of probability; he introduced the binomial coefficients and the binomial theorem in the Western world. He wrote more than 200 works on science.

Cardano partially invented and described several mechanical devices including the combination lock, the gimbal consisting of three concentric rings allowing a supported compass or gyroscope to rotate freely, and the Cardan shaft with universal joints, which allows the transmission of rotary motion at various angles and is used in vehicles to this day. He made significant contributions to hypocycloids - published in De proportionibus, in 1570. The generating circles of these hypocycloids, later named "Cardano circles" or "cardanic circles", were used for the construction of the first high-speed printing presses.

Orienteering is a group of sports in which participants use a map and compass to navigate from point to point in unfamiliar terrain as quickly as possible.

The sport originated from military land-navigation training in the late 19th century. It has since evolved into several competitive forms where participants race against the clock while navigating through checkpoints. Variants include automobile, underwater, mountain bike, ski, and trail orienteering. The most common form is foot orienteering, also known as FootO.

The Wujing Zongyao (Chinese: 武經總要), sometimes rendered in English as the Complete Essentials for the Military Classics, is a Chinese military compendium written from around 1040 to 1044.

The book was compiled during the Northern Song dynasty by Zeng Gongliang (曾公亮), Ding Du (丁度) and Yang Weide (楊惟德), whose writing influenced many later Chinese military writers. The compendium was published under the auspices of Emperor Renzong of Song, who also authored the book's preface. The book covers a wide range of subjects, including everything from naval warships to different types of catapults. It contains the earliest known written chemical formulas for gunpowder, made from saltpeter, sulphur and charcoal along with many added ingredients. In addition to formulas for gunpowder, the compendium also contains details on various other gunpowder weapons such as fire arrows, incendiary bombs and projectiles, and grenades and smoke bombs. It also describes an early form of the compass (using thermoremanence), and has the oldest illustration of a Chinese flamethrower with a double-action dual-piston cylinder-pump capable of shooting a continuous blast of flame.

Shen Kuo (Chinese: 沈括; 1031–1095) or Shen Gua, courtesy name Cunzhong (存中) and pseudonym Mengqi (now usually given as Mengxi) Weng (夢溪翁), was a Chinese polymath, scientist, and statesman of the Song dynasty (960–1279). Shen was a master in many fields of study including mathematics, optics, and horology. In his career as a civil servant, he became a finance minister, governmental state inspector, head official for the Bureau of Astronomy in the Song court, Assistant Minister of Imperial Hospitality, and also served as an academic chancellor. At court his political allegiance was to the Reformist faction known as the New Policies Group, headed by Chancellor Wang Anshi (1021–1085).

In his Dream Pool Essays or Dream Torrent Essays (夢溪筆談; Mengxi Bitan) of 1088, Shen was the first to describe the magnetic needle compass, which would be used for navigation (first described in Europe by Alexander Neckam in 1187). Shen discovered the concept of true north in terms of magnetic declination towards the north pole, with experimentation of suspended magnetic needles and "the improved meridian determined by Shen's [astronomical] measurement of the distance between the pole star and true north". This was the decisive step in human history to make compasses more useful for navigation, and may have been a concept unknown in Europe for another four hundred years (evidence of German sundials made circa 1450 show markings similar to Chinese geomancers' compasses in regard to declination).

The Dream Pool Essays (or Dream Torrent Essays) was an extensive book written by the Chinese polymath and statesman Shen Kuo (1031–1095), published in 1088 during the Song dynasty (960–1279) of China. Shen compiled this encyclopedic work while living in forced retirement from government office, naming the book after his private estate near modern Zhenjiang, Jiangsu province. The Dream Pool Essays was heavily reorganized in reprint editions by later Chinese authors from the late 11th to 17th centuries. In modern times it has been translated from Chinese into several languages. These include English, German, French, and Japanese translations.

The Dream Pool Essays covers a range of topics including discoveries and advancements in Traditional Chinese medicine, mathematics, astronomy, science and technology, optics, architecture and civil engineering, metallurgy, and early archaeology. Observations of the natural world included those of wildlife, meteorology, hypotheses advancing early ideas in geomorphology and climate change based on findings of petrification and natural erosion, and strange recorded phenomena such as the description of an unidentified flying object. In addition to establishing the theory of true north in magnetic declination towards the North Pole, Shen was also the first to record the use of a compass for navigation, the first to describe the invention of movable type printing by contemporary artisan Bi Sheng, and the first in China to describe a drydock for repairing boats out of water.

Bharuch (listen) is a city at the mouth of the Narmada River in Gujarat in western part of India. Bharuch is the administrative headquarters of Bharuch District.

The city of Bharuch and its surroundings have been settled since times of antiquity. It was a ship building centre and sea port in the pre-compass coastal trading routes for trading with the Occident and the East, perhaps as far back as the days of earliest trade connections. The route made use of the regular and predictable monsoon winds or relied on galleys. Many goods from the Far East and Far West (the famed Spices and Silk trade) were shipped there during the annual monsoon winds, making it a terminus for several key land-sea trade routes. Bharuch was known to the Greeks, the Parthian Empire, in the Roman Empire, the Chinese, and in other Western and Eastern centres of civilisation through the end of the European Middle Ages and other the middle ages of the world.

A guidance system is a virtual or physical device, or a group of devices implementing or controlling the movement of a ship, aircraft, missile, rocket, satellite, or any other moving object. Guidance is the process of calculating the changes in position, velocity, altitude, and/or rotation rates of a moving object required to follow a certain trajectory and/or altitude profile based on information about the object's state of motion.

A guidance system is usually part of a Guidance, navigation and control system, whereas navigation refers to the systems necessary to calculate the current position and orientation based on sensor data like those from compasses, GPS receivers, Loran-C, star trackers, inertial measurement units, altimeters, etc. The output of the navigation system, the navigation solution, is an input for the guidance system, among others like the environmental conditions (wind, water, temperature, etc.) and the vehicle's characteristics (i.e. mass, control system availability, control systems correlation to vector change, etc.). In general, the guidance system computes the instructions for the control system, which comprises the object's actuators (e.g., thrusters, reaction wheels, body flaps, etc.), which are able to manipulate the path and orientation of the object without direct or continuous human control.