This is a list of Korean inventions and discoveries; Koreans have made contributions to science and technology from ancient to modern times.
Agriculture Cheugugi
The first standardized rain gauge, called the cheugugi, was invented during the reign of Sejong the Great in the Joseon dynasty of Korea. The cheugugi was used throughout the country for official purposes. In the 15th century, Korea was the only country to use a quantitative measuring device for the purpose of meteorological observation. Heated greenhouse The first description of a heated greenhouse is from the Sanga Yorok, a treatise on husbandry compiled by a royal physician of the Joseon dynasty of Korea during the 1450s, in its chapter on cultivating vegetables during winter. The treatise contains detailed instructions on constructing a greenhouse that is capable of cultivating vegetables, forcing flowers, and ripening fruit within an artificially heated environment, by utilizing ondol, the traditional Korean underfloor heating system, to maintain heat and humidity; cob walls to insulate heat; and semi-transparent oiled hanji windows to permit light penetration for plant growth and provide protection from the outside environment. The Annals of the Joseon Dynasty confirm that greenhouse-like structures incorporating ondol were constructed to provide heat for mandarin orange trees during the winter of 1438. Korean hand plow The homi, which dates back to the Bronze Age, is one of the most representative agricultural tools of Korea. Its signature tapered blade was developed during the Later Silla period. In recent times, the homi (known by names such as the "Ho-Mi EZ Digger" and "Korean hand plow") has gained popularity in the West. Soybean cultivation The first unambiguously domesticated, cultigen-sized soybean was discovered in Korea at the Mumun-period Daundong site.
Aquaculture
Fishing net Limestone net sinkers discovered in Korea dating to 27,000 BC are the earliest evidence of fishing by nets and also the oldest fishing implements found to date in the world. Seaweed farming The earliest cultivation of gim, an edible seaweed, was started by Kim Yeo-ik () in the middle of the 17th century. Whaling The earliest depictions of whaling have been discovered in Korea at the Neolithic Bangudae site, which may date back to 6000 BC. Bangudae is the earliest evidence for whaling.
Mathematics
Chisanbop Chisanbop is an abacus-like calculation system using fingers that was invented in Korea in the 1940s and brought to the West in the 1970s. Hexagonal tortoise problem The hexagonal tortoise problem () was invented by Choi Seok-jeong during the Joseon period. Latin square The first literature on the Latin square dates back to the monograph Gusuryak () by the Joseon mathematician Choi Seok-jeong (1646–1715), predating Leonhard Euler by at least 67 years.
Science Social science
Double-entry bookkeeping system It is believed that the world's first double-entry bookkeeping system, called the sagae chibubeop, was developed in Goryeo and used by merchants in the capital of Kaesong, a center of trade and industry, at least two centuries earlier than in Italy. Public opinion polling In order to provide equality and fairness in taxation for the common people, Sejong the Great issued a royal decree to administer a nationwide public opinion poll regarding a new tax system called Gongbeop in 1430. Over the course of 5 months, the poll surveyed 172,806 people, of which approximately 57% responded with approval for the proposed reform. Society for the disabled The world's first society for the disabled, called the myeongtongsi (), was created by the Joseon government during the early Joseon period. The government-organized myeongtongsi regularly held events for the blind to participate in rituals and ceremonies and receive treatment for illnesses, donations of food and other items, and training for certain jobs. Parental leave In 1426, Sejong the Great enacted a law that granted government nobi women 100 days of maternity leave after childbirth, which, in 1430, was lengthened by one month before childbirth. In 1434, Sejong also granted the husbands 30 days of paternity leave. Silhak Silhak, also known as "Practical Learning", is a Korean school of thought developed by the seonbi that is dedicated to an empirical approach to statecraft based on pragmatism, instead of a blind and uncritical adherence to Confucianism. Silhak scholars, such as Chŏng Yagyong, emphasized human equality and advocated economic, educational, and social reform.
Life science Triangle of U In 1935, the Korean-Japanese plant scientist Woo Jang-choon proposed the Triangle of U, named after himself, which describes the evolution and relationships between members of the plant genus Brassica.
Architecture
Ondol One of the earliest systems of underfloor heating, dating back 2,500 years, was invented and widely used by Koreans. The Korean ondol heating system was thought to be the oldest of its kind until the recent archaeological discovery of a similar heating system in the Alaskan Aleutian Islands. However, the archaeologist who discovered it agrees with Korean researchers that the two systems developed independently, based on the distance of 5,000 kilometers and the absence of ondol in the areas between them. Some Korean researchers have explained this phenomenon by hypothesizing that a whale-hunting people from the Korean Peninsula migrated by sea to Alaska during prehistoric times. Inspired by the Korean ondol hydronic radiant floor heating system, the American architect Frank Lloyd Wright developed and introduced the first "radiant heating system" using hot water pipes. Seokbinggo The ancient Silla kingdom created an early refrigeration system called seokbinggo, which were subterranean chambers used to store ice and food. Korean fortress Koreans developed a unique and distinct fortress tradition. Korean fortresses were based on a stone culture and built with stones on natural mountainous terrain; therefore, they are conceptually completely different compared to Chinese fortresses, which were based on an earth culture and built with bricks and stamped earth on flat land. Korean fortresses were invented by Goguryeo and spread to Baekje and Silla, and then inherited and further developed by Goryeo and then Joseon. Goguryeo fortress ruins have been found in about 170 sites to date, including in China; one of the most notable among them is Ansi Fortress, which successfully defended against Tang Taizong during the Goguryeo–Tang War. Korea, beginning with Goguryeo, has been called "a country of fortresses"; almost 2,400 mountain fortress sites have been found in Korea. Korean-style fortresses can also be found in Japan, which were constructed and supervised by immigrants of Baekje origin. Korean pagoda Koreans created a unique and distinct pagoda tradition using stone. Pagodas were created in India using earth, then in China using wood, which spread to the Three Kingdoms of Korea, and then Japan; however, the pagoda tradition of East Asia diverged, with China creating pagodas using bricks, Korea creating pagodas using stone, and Japan continuing to use wood. Korean stone pagodas were first created in Baekje during the early 7th century and then inherited by Later Silla; 90% of the pagodas in Later Silla were made of stone. The stone pagoda tradition was propagated by the great abundance of high quality granite in Korea, which also led to other granite creations such as the Seokguram and Cheomseongdae. Goryeo, a devoutly Buddhist state, also inherited the stone pagoda tradition.
Astronomy Cheonsang Yeolcha Bunyajido The earliest known constellation patterns in Korea can be found on dolmens dating back to 3000 BC. The Cheonsang Yeolcha Bunyajido is a planisphere inscribed on black marble that was completed in 1395 during the reign of King Taejo; according to its inscription, it is based on a star chart from ancient Goguryeo that was lost during wartime. It is known as the world's second oldest star chart engraved in stone, after the Chinese Suzhou Star Chart of 1247. However, the Cheonsang Yeolcha Bunyajido's stellar positions indicate an epoch dating back to the first century CE, thus making it the oldest actual representation of the stars in the world. Cheomseongdae The Cheomseongdae is the oldest surviving astronomical observatory in Asia, and possibly the world. It was constructed in Seorabeol, the capital of Silla, during the reign of Queen Seondeok in the 7th century. Modeled on Baekje's Jeomseongdae, which now exists only in historical records, the Cheomseongdae influenced the construction of a Japanese observatory in 675, and Duke Zhou's observatory in China in 723.
Writing
Featural writing system Hangul is the world's first featural writing system, wherein the shapes of the letters are not arbitrary, but encode phonological features of the phonemes they represent. The Korean alphabet is unique among the world's writing systems, in that it combines aspects of featural, phonemic, and syllabic representation. Hangul, originally named Hunminjeongeum, was personally created by Sejong the Great to promote literacy among the common people. Phonemic orthography Predating the creation of Hangul by hundreds of years, Koreans created various phonetic writing systems that were used in conjunction with Hanja, including idu, hyangchal, gugyeol, and gakpil. Some of them may have influenced the development of kana in Japan.
Printing
Movable metal printing press The movable metal printing press was invented in the early thirteenth century in Goryeo (modern Korea); predating its introduction to Europe and presentation of the technology to the rest of the world by Johannes Gutenberg by over two centuries. The first ever book to be printed with the movable metal printing press was the Prescribed Ritual Texts of the Past and Present in 1234 during the Goryeo period. The earliest surviving book to be printed with movable metal type is Jikji, dated to 1377. The first lead type in the world is the Byeongjinja, created in 1436. Metal types were called juja (cast characters), and the Joseon government operated the jujaso bureau, a continuation of Goryeo's seojeogwon, to print books and documents to be distributed to the central and local administrations, village schools, scholars, and officials. Newspaper The Jobo, which is discussed in the Annals of the Joseon Dynasty, is possibly the oldest newspaper in the world. Published in 1577, the Jobo was a privately run commercial newspaper, printed daily, that covered a range of topics, including weather, constellations, and current affairs. In 2017, a Korean monk claimed to have discovered an extant copy of the Jobo.
Metallurgy Haifukiho Haifukiho (灰吹法, "ash-blowing method"), also known in Korea as the lead–silver separation method (Korean: 연은분리법; Hanja: 鉛銀分離法), is a cupellation technique for extracting silver from lead-bearing ore. An early Korean record appears in the Annals of the Joseon Dynasty in 1503, when Kim Gambul and Kim Geomdong presented a method for smelting lead to obtain silver. The method was introduced to Japan via Korea in 1533 and used at the Iwami Ginzan Silver Mine, where it greatly increased Japanese silver production.
Military
Iron plate armor Iron plate armor was used by Silla and Gaya beginning in the early 4th century. According to the Gyeongju National Museum, "The armor excavated from historic sites in Gujeongdong is plate armor, consisting of a number of long iron plates vertically linked with one another, a feature that is unique to armor found on the Korean Peninsula." Pistol