On the Internet, the well-known symbol "dog" (@) is used as a separator between a given user's name and the name of a domain (host) in the syntax of e-mail addresses.
Notoriety
Some Internet figures consider this symbol to be a signature of the common human communication space and one of the most popular signs in the whole world.
One of the evidence of the worldwide recognition of this designation can be called the fact that in 2004 (February) the International Telecommunication Union introduced into the common special code for designation @. It combines the codes of two C and A, which reflects their joint graphic writing.
History of the dog symbol
The Italian researcher Giorgio Stabile was able to find in the archives owned by the Institute of Economic History in the city of Prato (which is near Florence), a document in which this sign is first encountered in writing. Such an important testimony turned out to be a letter from a merchant from Florence, which was subsidized as early as 1536.
It refers to three merchant ships that arrived in Spain. The vessels' cargo included containers in which wine was transported, marked with the @ sign. After analyzing the data on the price of wine, as well as on the capacity of various medieval vessels, and comparing the data with the general system of measures used at that time, the scientist concluded that the @ sign was used as a special measuring unit that replaced the word anfora (translated "amphora"). This is how the universal measure of volume was called since ancient times.
Berthold Ullman's theory
Berthold Ullman is an American scientist who suggested that the @ symbol was developed by medieval monks in order to shorten the common word ad of Latin origin, which was often used as a universal term meaning "in relation", "in", "on".
It should be noted that in French, Portuguese and Spanish, the name of the designation comes from the term "arroba", which in turn denotes the Old Spanish measure of weight (about 15 kg), abbreviated in the letter with the @ symbol.
Modernity
Many people are interested in the name of the "dog" symbol. Note that the official modern name of this symbol sounds like "commercial at" and originates from the accounts in which it was used in the following context: [email protected]$ 2each = $ 14. This can be translated as 7 pieces of $ 2 = $ 14
Since the dog symbol was used in business, it was placed on the keyboards of all typewriters. He even attended "Underwood", which was released back in 1885. It was only after 80 long years that the first computer keyboards inherited the dog symbol.
Internet
Let's turn to the official history of the World Wide Web. She claims that the Internet dog symbol in e-mail addresses originated from an American engineer and computer scientist named Ray Tomlinson, who in 1971 managed to send the first ever e-mail message across the network. In this case, the address had to be composed of two parts - the name of the computer through which the registration was made, and the username. Tomilson chose the "dog" character on the keyboard as a separator between the specified parts, since it was not part of either computer names or usernames.
Versions of the origin of the famous name "dog"
There are several possible versions of the origin of such a funny name in the world. First of all, the badge really looks a lot like a curled up dog.
In addition, the abrupt sound of the word at (the symbol for a dog in English is read this way) resembles a bit of a dog barking. It should also be noted that with a good imagination, you can see in the symbol almost all the letters that are part of the word "dog", except perhaps, excluding "k".
However, the following legend can be called the most romantic. A long time ago, in that good time, when all computers were very large, and screens were purely text-based, there was one popular game in the virtual kingdom, which got a name that reflects its content - "Adventure" (Adventure).
Its meaning was to travel through a maze created by a computer in search of various treasures. There were, of course, battles with underground harmful creatures. The maze on the display was drawn using the symbols "-", "+", "!", And the player, hostile monsters and treasures were designated by various icons and letters.
Moreover, according to the plot, the player was friends with a faithful helper - a dog, who could always be sent for reconnaissance in the catacombs. That one was designated just by the @ sign. Was this the root cause of the now generally accepted name, or, on the contrary, was the icon chosen by the developers of the game, because it was already called that? The legend does not give answers to these questions.
What is the name of the virtual "dog" in other countries?
It is worth noting that in our country the symbol "dog" is also called a ram, an ear, a bun, a frog, a dog, and even a mallard. In Bulgaria, it is "maymunsko a" or "klomba" (monkey A). In the Netherlands - apenstaartje. In Israel, the sign is associated with a whirlpool (strudel).
The Spanish, French and Portuguese call the designation in the same way as the measure of weight (respectively: arroba, arrobase and arrobase). If you ask about the meaning of the dog symbol among the inhabitants of Poland and Germany, they will answer you that it is a monkey, a paper clip, a monkey's ear or a monkey's tail. It is considered a snail in Italy, calling it chiocciola.
The least poetic names were given to the symbol in Sweden, Norway and Denmark, calling it "snout a" (snabel-a) or elephant's tail (tailed a). The most appetizing name can be considered a variant of the Czechs and Slovaks, who consider the sign to be a herring under a fur coat (rollmops). The Greeks also associate with the cuisine, calling the designation "little pasta".
For many it is still a monkey, namely for Slovenia, Romania, Holland, Croatia, Serbia (maјmun; alternative: "crazy A"), Ukraine (alternatives: snail, doggie, dog). The term Lithuania (eta - "eta", borrowing with the addition of a Lithuanian morpheme at the end) and Latvia (et - "et") were borrowed from the English language. The variant of the Hungarians, where this cute sign became a tick, can be disheartening.
Finland (cat's tail), America (cat), Taiwan and China (mouse) play cat and mouse. Residents of Turkey (rose) turned out to be romantics. And in Vietnam this badge is called "crooked A".
Alternative hypotheses
It is believed that the name of the designation "dog" in Russian speech appeared thanks to the famous DCK computers. In them, the "dog" appeared during computer boot. Indeed, the designation resembled a small dog. All DVK users, without saying a word, came up with a name for the symbol.
It is curious that the original spelling of the Latin letter "A" was supposed to decorate it with curls, thus it was very similar to the current spelling of the "doggy" sign. The translation of the word "dog" into the Tatar language sounds like "et".
Where else can you find a "dog"?
There are a number of services that use this symbol (besides email):
HTTP, FTP, Jabber, Active Directory. In IRC, the symbol is placed before the name of the channel operator, for example @oper.
The sign is also widely used in the main programming languages. In Java, it is used to declare annotation. In C #, it is needed to escape characters in a string. The operation of taking an address is appropriately denoted in Pascal. For Perl, this is an array identifier, and in Python, accordingly, a decorator declaration. The field identifier for an instance of a class is a Ruby sign.
As for PHP, here the "doggie" is used in order to suppress the output of an error, or to warn about a task that has already occurred at the time of execution. The symbol became the prefix for indirect addressing in MCS-51 assembler. In XPath, it is shorthand for the attribute axis, which selects a set of attributes for the current element.
Finally, Transact-SQL assumes that the local variable name must begin with @ and the global variable name must begin with @. In DOS, thanks to the symbol, echo is suppressed for the executable command. The designation of an action like echo off mode is usually used before entering mode to prevent a specific command from being printed to the screen (for clarity: @echo off).
So we looked at how many aspects of virtual and real life depend on an ordinary symbol. However, let's not forget that it became the most recognizable thanks to the emails that are sent in thousands every day. We can assume that today you will receive a letter with a "dog", and it will bring only good news.
The signs that are designed to divide words into groups that are convenient for our perception are called punctuation (from Latin punctus, that is, a point). Such signs bring order to these very groups, help to correctly interpret the text and prevent false perception of words, phrases and sentences.
But it was not always so. Until the mid-17th century, punctuation meant writing dots near consonants. Such dots represent vowel sounds in written Hebrew. And in Latin, the spelling of signs had such a name as dotting. The exchange of these values took place around the middle of the 17th century.
Several thousand years ago, words were not separated from each other by spaces, and the text was not separated by adding periods. In the 5th century BC. some Greek writers used separate punctuation marks in their texts. The pointed mark is found in the writings of Euripides. With this sign, the playwright denoted the change of the speaking hero. The philosopher Plato ended some sections of his books with a colon.
Aristotle was the first to invent the punctuation mark, which carried the function of changing the semantic meaning in the text. It bore the name of the paragraphos, which meant "writing on the side." This sign was indicated by a horizontal line that was at the bottom at the beginning of the line.
In the 1st century, the Romans already actively used dots in writing, and they designated paragraphs as follows: the Romans wrote the first few letters of the new part of the text in the margins. By the end of the Middle Ages, the letter "c" (abbreviated capitulum - chapter) began to be put in this place.
It wasn't until the 17th century that paragraphs were indented and line skipped. Dividing semantic segments using signs began around 194 BC. It was at this time that Aristophanes of Alexandria created a three-point system, which was used when dividing the text into segments of different sizes.
The lower point, "comma", was placed at the end of a short segment, the point above, "periodos", was used when dividing the text into large parts. The middle segments were separated by a point in the middle, "columns". Presumably Aristophanes was the first to use a hyphen to write compound words and a slash, which was placed next to words with obscure meaning.
But such innovations in punctuation have not found widespread use. They were used periodically until the 8th century, when scribes had already begun to separate words from each other and to use attributed letters. But reading the text without punctuation marks and with letters of different sizes was not very convenient, and Alcuin, an Anglo-Saxon scholar, reformed the system and introduced some additions. Some of them reached England, where punctuation marks appeared around the 10th century. In the manuscripts of that time, they were used to indicate a change in intonation and a pause.
Ald Manucius, a Venetian printer, at the end of the 15th century became the author of punctuation marks, which have survived to this day unchanged. For example: period, colon and semicolon.
The grandson of the famous printer Ald Manutius the Younger 60 years later, for the first time designated punctuation marks as auxiliary. On these signs, he entrusted the function of determining the structure of the sentence.
Road signs are an integral part of roads and their order. It's hard to imagine life without them. And recently I wondered where they came from, who and how invented them.
But first things first.
First signs
There are many hypotheses about the earliest pointers. It is believed that primitive people made routes through forests and open areas, leaving small stone piles, making notches in trees or breaking branches.
Not the best option. Marks, branches and stones are not always visible.
Next step
Further, people decided to put pillars with sculpted heads of gods, statesmen and philosophers so that they would contrast with natural landscapes. Over time, signs of settlements were added to the signs.
Officially, the first system of road signs originated in ancient Rome. Cylindrical milestones were installed on the roads. They had information about the distance from the Roman Forum, where the golden milepost was located. Therefore, "all roads lead to Rome."
From there, the milepost system spread everywhere. Although we have pointers appeared rather late: only in the time of Peter I.
New impetus
The first rules of the road in the modern sense appeared in Portugal in 1686. In the narrow streets of Lisbon, priority signs were installed to regulate traffic flows.
Large scale road signs began to be installed for fast and quiet cyclists in the 1870s. The markers did not provide distance information, but warned, for example, of steep hills.
With the development of the automotive industry, it was decided to revise the road sign system. In 1895, the Italian Tourist Club completed the development of the first. In 1903, the first signs were installed in Paris.
Standardization failed
And then it began. Who is in that much. Each country had its own road signs. However, car traffic to other countries has become commonplace. There was an urgent need to introduce signs of international importance.
So, in Paris in 1909, the "International Convention on the Movement of Cars" adopted the following road signs: "Rough road", "Winding road", "Crossroads", "Crossing with the railway".
Since 1926, international road signs have been intensively developed, they have been changed and supplemented. But whatever one may say, the signs in different countries are different. In some Chinese or Japanese, you can't understand anything at all without knowing the language.
Who invented them
Road signs were not invented overnight. They have evolved and modified over the years.
Different types of pointers that are understandable to everyone were developed by more than one person. This work involved car users and government committees to create easily recognizable signs. Any business needs a focus group, and traffic rules are no exception.
Last bit of humor
Today it is very popular to stick different people, animals and more on signs, giving them a cheerful and extraordinary look. I know for sure that there are many of them in Italy.
And depending on the terrain, signs may warn of wildlife that runs out on the road: moose, bears, kiwi, crocodiles, penguins and other animals. Plus there are funny ones, such as “you can't go to the toilet in a big way in the forest”, “reproductive zone, don't bother the kangaroo” or “you can't hunt killer whales” in the desert.
So it goes. Have you noticed unusual signs in other countries?
Description of the presentation for individual slides:
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History of the origin of mathematical signs Prepared by: Ivan Cherepanov, student 5 Grade A mathematics teacher: Mosunova O.A. As there are no tables in the world without table legs, As there are no goats without horns, Cats without whiskers and crayfish shells, So there are no actions in arithmetic without signs!
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Objectives To consider where the mathematical signs came to us and what they originally meant. Compare mathematical signs of different nations. Consider the similarity of modern mathematical signs to those of our ancestors
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Object: mathematical signs of different peoples. Basic research methods: literature analysis, comparison, survey of students, analysis and generalization of the data obtained in the course of the research.
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Why in our time we use just such mathematical signs: + "plus", - "minus", ∙ "multiplication" and: "division", and not some others? Problem
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Hypothesis I think that mathematical signs arose simultaneously with the appearance of numbers and numbers
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The origin of mathematical signs The origin of these signs can not always be precisely determined. Symbols for arithmetic operations of addition (plus “+’ ’”) and subtraction (minus “-‘ ’) are so common that we almost never think that they did not always exist. Indeed, someone had to invent these symbols (or at least others that later evolved into the ones we use today). Surely, it also took some time before these symbols became generally accepted. It is believed that the signs "+" and "-" have arisen in trade practice. The wine merchant marked with lines how many measures of wine he sold from the barrel. Adding new supplies into the barrel, he crossed out as many expendable lines as he restored measures. So, supposedly, signs of addition and subtraction occurred in the 15th century. There is another explanation regarding the origin of the "+" sign. Instead of "a + b" they wrote "a and b", in Latin "a et b". Since the word "et" ("and") had to be written very often, they began to shorten it: first they wrote one letter t, which eventually turned into a "+"
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The algebraic sign “-” The first use of the modern algebraic sign “+” refers to a German manuscript on algebra from 1481, which was found in the Dresden library. In a Latin manuscript from the same time (also from the Dresden library), there are both symbols: + and -. It is known that Johann Widmann reviewed and commented on both of these manuscripts. In 1489, he published in Leipzig the first printed book (Mercantile Arithmetic), in which both the + and - signs were present (see figure). The fact that Widmann used these symbols as if they were common knowledge points to the possibility of their origin in commerce. An anonymous manuscript, apparently written at about the same time, also contains the same symbols, and this provided the publication of two additional books, published in 1518 and 1525.
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Some mathematicians, such as Record, Harriot, and Descartes, used the same sign. Others (such as Hume, Huygens, and Fermat) used the Latin cross “†’ ”, sometimes horizontal, with a crossbar at one end or the other. Finally, some (like Halley) used the more decorative Widman look.
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The first occurrence of "+" and "-" in English is found in the 1551 book on algebra, The Whetstone of Witte, by the Oxford mathematician Robert Record, who also introduced an equal sign that was much longer than the current sign. In the description of the plus and minus signs, Record wrote: “Often there are two other signs, the first of which is written“ + ”and means more, and the second“ - ”and means less.
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Subtraction sign The subtraction notation was a little less fancy, but perhaps more confusing (for us, at least), since instead of the simple “-” sign, German, Swiss and Dutch books sometimes used the symbol “÷”, which we now denote division. Several books of the seventeenth century (eg Halley and Mersenne) use two dots “∙ ∙’ ”or three dots“ ∙ ∙ ∙ ’’ ”to denote subtraction.
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In Ancient Egypt In the famous Egyptian papyrus of Ahmes, a pair of feet going forward denotes addition, and those going out denote subtraction
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The ancient Greeks denoted addition by writing side by side, but from time to time they used the forward slash symbol “/” and a semi-elliptic curve for subtraction. used in Bakhshali's manuscript Arithmetic (probably the third or fourth century).
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In the late fifteenth century, the French mathematician Schuecke (1484) and the Italian Pacioli (1494) used “p” (meaning “plus”) for addition “m” (meaning “minus”) for subtraction. Schuecke
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In Italy In Italy, the symbols "+" and "-" were adopted by the astronomer Christopher Clavius (German who lived in Rome), mathematicians Gloriosi and Cavalieri in the early seventeenth century Christopher Clavius
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The sign of multiplication To denote the action of multiplication, some of the European mathematicians of the 16th century used the letter M, which was the initial in the Latin word for increase, multiplication, - animation (from this word the name "cartoon" comes from). In the 17th century, some mathematicians began to denote multiplication with an oblique cross "×", while others used a dot for this. In Europe, for a long time, the product was called the sum of multiplication. The name "multiplier" is mentioned in the works of the XI century. For millennia, the action of division was not indicated by signs. The Arabs introduced a dash "/" to indicate division. It was adopted from the Arabs in the 13th century by the Italian mathematician Fibonacci. He was the first to use the term "private". The colon sign ":" to denote division came into use at the end of the 17th century. In Russia, the names "dividend", "divisor", "quotient" were first introduced by L.F. Magnitsky at the beginning of the 18th century. The multiplication sign was introduced in 1631 by William Oughtred (England) in the form of an oblique cross. Before him, the letter M was used. Later, Leibniz replaced the cross with a dot (end of the 17th century) so as not to confuse it with the letter x; before him, such symbolism was found in Regiomontanus (15th century) and the English scientist Thomas Harriott (1560-1621).
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Division signs Otred preferred the forward slash "/". Leibniz began to denote division with a colon. Before them, the letter D was also often used. Beginning with Fibonacci, a fraction line is also used, which was used even in Arabic writings. In England and the USA, the symbol ÷ (obelus) became widespread, which was proposed by Johann Rahn and John Pell in the middle of the 17th century.
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Equality and Inequality Signs The equal sign was denoted at different times in different ways: both in words and in different symbols. The sign "=", so convenient and understandable now, came into general use only in the 18th century. And the English author of the algebra textbook Robert Rickord proposed this sign to denote the equality of two expressions in 1557. He explained that there is nothing more equal in the world than two parallel segments of the same length. In continental Europe, the equal sign was introduced by Leibniz. The not equal sign was first encountered by Euler. Comparison signs were introduced by Thomas Harriot in his work, published posthumously in 1631. Before him, they wrote in words: more, less.
From the Indian icons shown in the bottom line (script of the 1st century A.D.) modern numbers originated
To designate the numbers from 1 to 9 in India from the VI century BC. NS. the spelling "brahmi" was used, with separate characters for each digit. Having changed somewhat, these icons became modern numbers that we call Arab, and the Arabs themselves - Indian .
The decimal point, which separates the fractional part of a number from the whole, was introduced by the Italian astronomer Magini (1592) and Napier (1617). Previously, instead of a comma, other symbols were put - a vertical bar: 3 | 62, or zero in brackets: 3 (0) 62
"Two-level" record of an ordinary fraction (for example) was still used by ancient Greek mathematicians, although their denominator was written as an enumerator, and there was no fraction. Indian mathematicians have moved the numerator to the top; through the Arabs, this format was adopted in Europe. The fractional line was first introduced in Europe by Leonardo of Pisa (1202), but it came into use only with the support of Johann Widmann (1489).
The plus and minus signs were apparently invented in the German mathematical school of "kossists" (that is, algebraists). They are used in Johann Widmann's textbook, A Quick and Nice Counting for All Traders, published in 1489. Before that, addition was denoted by the letter p(plus) or Latin word et(the conjunction "and"), and subtraction is a letter m(minus)
The multiplication sign was introduced in 1631 by William Oughtred (England) in the form of an oblique cross. Before him, the letter M was most often used, although other designations were proposed: the symbol of a rectangle (Erigon, 1634), an asterisk (Johann Ran, 1659). Later, Leibniz replaced the cross with a dot (end of the 17th century) so as not to confuse it with the letter x; before him, such symbolism was found in Regiomontanus (15th century) and the English scientist Thomas Harriott (1560-1621).
Division signs. Otred preferred the forward slash. Leibniz began to denote division with a colon.
The plus or minus sign appeared in Girard (1626) and Oughtred. True, Girard also wrote between plus and minus with the words “or”.
Exponentiation. The modern notation of the exponent was introduced by Descartes in his "Geometry" (1637), however, only for natural degrees greater than 2.
The sum sign was introduced by Euler in 1755.
The sign of the product was introduced by Gauss in 1812.
Letter ias an imaginary unit code:suggested by Euler (1777), who took for this the first letter of the word imaginarius (imaginary).
The notation for the absolute value and modulus of a complex number appeared in Weierstrass in 1841. In 1903, Lorenz used this same symbology for vector length.
=
First printed appearance of an equal sign (equation written)
Equals sign proposed by Robert Record in 1557
The sign "approximately equal" was invented by the German mathematician S. Gunther in 1882.
The not equal sign was first encountered by Euler.
The author of the "identically equal" sign is Bernhard Riemann (1857). The same symbol, according to Gauss's proposal, is used in number theory as a sign of comparison modulo, and in logic - as a sign of an equivalence operation.
Comparison signs were introduced by Thomas Harriott in his work, published posthumously in 1631. Before him, they wrote in the words: more, smaller.
The symbols for a loose comparison were proposed by Wallis in 1670.
The symbols "angle" and "perpendicular" were invented in 1634 by the French mathematician Pierre Erigon. Erigon's angle symbol resembled a badge, modernized by William Oughtred (1657).
Modern designations of angular units (degrees, minutes, seconds) are found in the "Almagest" by Ptolemy.Radian measure of angles, more convenient for analysis , suggested in 1714 by the English mathematician Roger Coots. The term itself radianinvented in 1873 by James Thomson, brother of the famous physicist Lord Kelvin.
The generally accepted designation of the number 3.14159 ... was first formed by William Jones in 1706, taking the first letter of the Greek words. περιφρεια is a circle and περμετρος is a perimeter, that is, the length of a circle. This abbreviation was liked by Euler, whose works finally consolidated the designation.
Abbreviated notation for sine and cosine was introduced by Otred in the middle of the 17th century.
Abbreviated notation for tangent and cotangent: introduced by Johann Bernoulli in the 18th century, they became widespread in Germany and Russia. In other countries, the names of these functions are used, proposed by Albert Girard even earlier, at the beginning of the 17th century.
The manner of denoting inverse trigonometric functions with the prefix arc(from lat. arcus, arc) appeared in the work of the Austrian mathematician Karl Scherfer (German. Karl scherffer; 1716-1783) and gained a foothold thanks to Lagrange. It meant that, for example, an ordinary sine allows finding a chord that contracts it along an arc of a circle, and the inverse function solves the opposite problem. Until the end of the 19th century, the English and German mathematical schools proposed other designations:, but they did not take root.
The partial derivative symbol was first made commonly used by Karl Jacobi (1837), and then by Weierstrass, although this designation had already been encountered earlier in one work by Legendre (1786).
The limit symbol appeared in 1787 by Simon Luillier and received the support of Cauchy (1821) ... The argument limit value was first specified separately, after the symbollim, not under it. Weierstrass introduced a designation close to the modern designation, however, instead of the usual arrow, he used the equal sign ... The arrow appeared at the beginning of the 20th century at once by several mathematicians - for example, by Hardy (1908).
The symbol for this differential operator was invented by William Rowan Hamilton (1853), and the name "nabla" was suggested by Heaviside (1892).
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