Have a deep view into what people are curious about.

🔗 Computing 🔗 Computing/Software 🔗 Computer graphics

Xsnow is a software application that was originally created as a virtual greeting card for Macintosh systems in 1984. In 1993, the concept was ported to the X Window System as Xsnow, and was included on a number of Linux distributions in the late 1990s.

🔗 London 🔗 Holidays 🔗 Christianity 🔗 River Thames 🔗 Christianity/Christmas

The River Thames frost fairs were held on the tideway of the River Thames in London, England in some winters, starting at least as early as the late 7th century all the way until the early 19th century. Most were held between the early 17th and early 19th centuries during the period known as the Little Ice Age, when the river froze over most frequently. During that time the British winter was more severe than it is now, and the river was wider and slower, further impeded by the medieval Old London Bridge.

Even at its peak, in the mid-17th century, the Thames in London froze less often than modern legend sometimes suggests, never exceeding about one year in ten except for four winters between 1649 and 1666. From 1400 until the removal of the medieval London Bridge in 1835, there were 24 winters in which the Thames was recorded to have frozen over at London; if "more or less frozen over" years (in parentheses) are included, the number is 26: 1408, 1435, 1506, 1514, 1537, 1565, 1595, 1608, 1621, 1635, 1649, 1655, 1663, 1666, 1677, 1684, 1695, 1709, 1716, 1740, (1768), 1776, (1785), 1788, 1795, and 1814. Of the 24, the numbers in each century were: 15th two, 16th five, 17th ten, 18th six, 19th one. The Thames freezes over more often upstream, beyond the reach of the tide, especially above the weirs, of which Teddington Lock is the lowest. The last great freeze of the higher Thames was in 1962–63.

Frost fairs were a rare event even in the coldest parts of the Little Ice Age. Some of the recorded frost fairs were in 695, 1608, 1683-4, 1716, 1739–40, 1789, and 1814. Recreational cold weather winter events were far more common elsewhere in Europe, for example in the Netherlands. These events in other countries as well as the winter festivals and carnivals around the world in present times can also be considered frost fairs. However, very few of them have actually used that title.

During the Great Frost of 1683–84, the severest frost recorded in England, the Thames was completely frozen for two months, with the ice reaching a thickness of 11 inches (28 cm) in London. Solid ice was reported extending for miles off the coasts of the southern North Sea (England, France and the Low Countries), causing severe problems for shipping and preventing the use of many harbours.

🔗 Physics 🔗 Astronomy

In astrophysics and physical cosmology, Olbers' paradox, named after the German astronomer Heinrich Wilhelm Olbers (1758–1840), also known as the "dark night sky paradox", is the argument that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. In the hypothetical case that the universe is static, homogeneous at a large scale, and populated by an infinite number of stars, then any line of sight from Earth must end at the (very bright) surface of a star and hence the night sky should be completely illuminated and very bright. This contradicts the observed darkness and non-uniformity of the night.

The darkness of the night sky is one of the pieces of evidence for a dynamic universe, such as the Big Bang model. That model explains the observed non-uniformity of brightness by invoking spacetime's expansion, which lengthens the light originating from the Big Bang to microwave levels via a process known as redshift; this microwave radiation background has wavelengths much longer than those of visible light, so appears dark to the naked eye. Other explanations for the paradox have been offered, but none have wide acceptance in cosmology.

🔗 Internet 🔗 Novels

Victory Garden is a work of electronic literature by American author Stuart Moulthrop. It was written in StorySpace and published by Eastgate Systems in 1992. It is often discussed along with Michael Joyce's afternoon, a story as an important work of hypertext fiction.

🔗 Mathematics

In symbolic computation (or computer algebra), at the intersection of mathematics and computer science, the Risch algorithm is an algorithm for indefinite integration. It is used in some computer algebra systems to find antiderivatives. It is named after the American mathematician Robert Henry Risch, a specialist in computer algebra who developed it in 1968.

The algorithm transforms the problem of integration into a problem in algebra. It is based on the form of the function being integrated and on methods for integrating rational functions, radicals, logarithms, and exponential functions. Risch called it a decision procedure, because it is a method for deciding whether a function has an elementary function as an indefinite integral, and if it does, for determining that indefinite integral.

The complete description of the Risch algorithm takes over 100 pages. The Risch–Norman algorithm is a simpler, faster, but less powerful variant that was developed in 1976 by Arthur Norman.

🔗 Biography 🔗 France 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Biography/arts and entertainment 🔗 Christianity 🔗 Catholicism 🔗 Middle Ages/Crusades 🔗 Military history/Crusades 🔗 Belgium 🔗 Christianity/Christianity in China

William of Rubruck (Dutch: Willem van Rubroeck, Latin: Gulielmus de Rubruquis; fl. 1248–1255) was a Flemish Franciscan missionary and explorer.

He is best known for his travels to various parts of the Middle East and Central Asia in the 13th century, including the Mongol Empire. His account of his travels is one of the masterpieces of medieval travel literature, comparable to those of Marco Polo and Ibn Battuta.

🔗 Religion 🔗 Bible 🔗 Linguistics

In corpus linguistics, a hapax legomenon ( also or ; pl. hapax legomena; sometimes abbreviated to hapax) is a word that occurs only once within a context, either in the written record of an entire language, in the works of an author, or in a single text. The term is sometimes incorrectly used to describe a word that occurs in just one of an author's works, but more than once in that particular work. Hapax legomenon is a transliteration of Greek ἅπαξ λεγόμενον, meaning "(something) being said (only) once".

The related terms dis legomenon, tris legomenon, and tetrakis legomenon respectively (, , ) refer to double, triple, or quadruple occurrences, but are far less commonly used.

Hapax legomena are quite common, as predicted by Zipf's law, which states that the frequency of any word in a corpus is inversely proportional to its rank in the frequency table. For large corpora, about 40% to 60% of the words are hapax legomena, and another 10% to 15% are dis legomena. Thus, in the Brown Corpus of American English, about half of the 50,000 distinct words are hapax legomena within that corpus.

Hapax legomenon refers to a word's appearance in a body of text, not to either its origin or its prevalence in speech. It thus differs from a nonce word, which may never be recorded, may find currency and may be widely recorded, or may appear several times in the work which coins it, and so on.

🔗 Computing 🔗 Computer science

Eiffel is an object-oriented programming language designed by Bertrand Meyer (an object-orientation proponent and author of Object-Oriented Software Construction) and Eiffel Software. Meyer conceived the language in 1985 with the goal of increasing the reliability of commercial software development; the first version becoming available in 1986. In 2005, Eiffel became an ISO-standardized language.

The design of the language is closely connected with the Eiffel programming method. Both are based on a set of principles, including design by contract, command–query separation, the uniform-access principle, the single-choice principle, the open–closed principle, and option–operand separation.

Many concepts initially introduced by Eiffel later found their way into Java, C#, and other languages. New language design ideas, particularly through the Ecma/ISO standardization process, continue to be incorporated into the Eiffel language.

🔗 Novels 🔗 Children's literature 🔗 Novels/Short story

Winnie-the-Pooh (1926) is the first volume of stories about Winnie-the-Pooh, written by A. A. Milne and illustrated by E. H. Shepard. The book focuses on the adventures of a teddy bear called Winnie-the-Pooh and his friends Piglet, a small toy pig; Eeyore, a toy donkey; Owl, a live owl; and Rabbit, a live rabbit. The characters of Kanga, a toy kangaroo, and her son Roo are introduced later in the book, in the chapter entitled "In Which Kanga and Baby Roo Come to the Forest and Piglet has a Bath". The bouncy toy-tiger character of Tigger is not introduced until the sequel, The House at Pooh Corner.

In 2003, Winnie the Pooh was listed at number 7 on the BBC's survey The Big Read.

🔗 China

Counting rods (traditional Chinese: 籌; simplified Chinese: 筹; pinyin: chóu; Japanese: 算木; rōmaji: sangi; Korean: sangaji) are small bars, typically 3–14 cm long, that were used by mathematicians for calculation in ancient East Asia. They are placed either horizontally or vertically to represent any integer or rational number.

The written forms based on them are called rod numerals. They are a true positional numeral system with digits for 1–9 and a blank for 0, from the Warring states period (circa 475 BCE) to the 16th century.